Canadian GDP Essays - Currency, Economic Indicators,

Training in Clinical and Counseling Psychology

Preparing in Clinical and Counseling Psychology Graduate school candidates who need a profession in the field of brain science regularly expect that preparation in clinical or directing brain research will set them up for training, which is a sensible suspicion, yet not every doctoral program offer comparative preparing. There are a few sorts of doctoral projects in clinical and guiding brain research, and every offer diverse preparing. Consider what you need to do with your degree counsel patients, work in the scholarly world or do inquire about when you choose which program is best for you. Contemplations in Selecting Graduate Programsâ As you consider applying to clinical and directing projects recall your own advantages. What do you would like to do with your degree? Would you like to work with individuals and practice brain science? Would you like to educate and direct research at a school or college? Would you like to direct research in business and industry or for the legislature? Would you like to work in open approach, leading and applying exploration to address social issues? Not all doctoral brain research projects will prepare you for these professions. There are three sorts of doctoral projects in clinical and directing brain research and ​two diverse scholastic degrees. Researcher Model The researcher model accentuates preparing understudies for investigate. Understudies procure a Ph.D., a specialist of philosophy,â which is an exploration degree. Like other science Ph.Ds., clinical and advising therapists prepared in researcher programs center around directing exploration. They figure out how to ask and answer inquiries through leading painstakingly structured research. Alumni of this model land positions as specialists and school teachers. Understudies in researcher programs are not prepared by and by and, except if they look for extra preparing after graduation, they are not qualified to rehearse brain science as specialists. Researcher Practitioner Model The researcher professional model is otherwise called the Boulder Model, after the 1949 Boulder Conference on Graduate Education in Clinical Psychology in which it was first made. Researcher expert projects train understudies in both science and practice. Understudies procure Ph.D.s and figure out how to plan and direct research, yet they additionally figure out how to apply investigate discoveries and practice as clinicians. Graduates have vocations in the scholarly community and practice. Some work as scientists and educators. Others work by and by settings, for example, medical clinics, psychological well-being offices, and private practice. Some do both. Professional Scholar Model The specialist researcher model is additionally alluded to as the Vail model, after the 1973 Vail Conference on Professional Training in Psychology, when it was first explained. The expert researcher model is an expert doctoral qualification that trains understudies for clinical practice. Most understudies gain Psy.D. (specialist of brain research) degrees. Understudies figure out how to comprehend and apply academic discoveries to rehearse. They are prepared to be customers of research. Graduates work practically speaking settings in clinics, psychological well-being offices, and private practice.

Aiims and Objectives Free Essays

Assignment 1 †The points and destinations of Tesco Nike Aims: A point is an objective of which a business needs to accomplish. For instance, a few organizations intend to grow while others expect to endure. Another point that a business can have is selling however much as could be expected while others plan to improve the nature of their items. We will compose a custom exposition test on Aiims and Objectives or then again any comparable theme just for you Request Now Objective: A goal is the thing that a business needs to accomplish however more exact focuses than point. For instance a goal for a business can be to sell 1000 a greater number of items than we sold a year ago, sell a larger number of items than its rivals, make ? 0,000 more benefit than the earlier year. Point versus Objective: The distinction between a point and a goal is that a goal is more exact and quantifiable than a point. For instance a point can be to make more benefit, while a goal can be to make ? 10,000 more benefit than the earlier year. The best sort of targets is a SMART goal. Savvy represents the accompanying; S †Specific M †Measurable A †Agreed R †Realistic T †Time compelled A case of a SMART goal is ‘to increment in deals of natural items to ? 1 billion by 2006’. This is a particular target, it is likewise quantifiable and is time obliged it must be accomplished by 2006, given client enthusiasm for natural item, it is additionally reasonable, and if this goal has additionally been concurred with providers and senior supervisors, this it is a SMART goal, yet in the event that Tesco had simply said it needed ‘to increment deals of natural product’ then this isn't SMART, and it additionally can't be estimated without any problem. Why a goal must be quantifiable? A goal of a business must be quantifiable so as to check whether the business has arrived at its point, be that as it may on the off chance that it is vital a business can change its target so as to meet its point. A business can make its goal quantifiable; rather than saying we will make more benefit. A business can make its target quantifiable by giving it an opportunity to quantify; in this manner a quantifiable goal can be we will make ? 10,000 more benefit than the earlier year. Points of Nike: †¢ Nike is planning to update its benefit by over half in the following five years. From the Internet. †¢ Nike is pointing on growing ease canvas footwear in creating nations in the following 3 years. From the Internet. †¢ Nike is expecting to keep their image as the biggest sportswear brand on the planet, by forestalling Adidas from surpassing them. From the Internet. †¢ By the following year Nike is planning to appear in its adverts, and yearly reports that it means well with respect to working conditions. From the Internet. †¢ Nike is focusing on half Revenue Growth over Next Five Years. From the Internet. †¢ Nike is meaning to overhaul its volume over half in the following fives years. From the Internet. Points of Tesco: †¢ Tesco is meaning to redesign its benefit by over half in the following five years. From the Internet. †¢ Tesco is planning to comprehend their clients superior to anybody in the following 3 years. From the Internet. Tesco is expecting to make their organization the biggest grocery store in the following 8 years, by eclipsing worldwide contenders, for example, Wal-Mart and Carrefour. From the Internet. †¢ Tesco are planning to give 150 more natural items than the earlier year. From the Internet. †¢ By the following year Tesco is meaning to appear in its adverts, and yearly reports that it means well with respect to working conditions. From the Internet. Points and destinations of Tesco and Nike: All kinds of organizations including Tesco and Nike must be expertly sorted out so as to accomplish the points and goals that it has set itself. Organizations including Tesco and Nike must have expects to discover which office that they have to improve in, so as to improve the business overall. Organizations including Tesco and Nike must make destinations to discover how they will accomplish the points that it has set itself. Why the points and destinations of Nike and Tesco contrast: The points and goals of my two picked association which are called Tesco and Nike vary in light of the fact that Tesco is progressively similar to a grocery store which sells nourishments, and furthermore non-food products and ventures, for example, gems, books, CDs, and garments. While Nike is progressively similar to a monster sports association which doesn’t sell non-food merchandise, however it sells sports items, for example, coaches and garments. The primary goal of Nike is to ensure and improve Nike’s position as the main athletic brand in America and around the globe; this demonstrates Nike has the aspiration to make their association as large as could be expected under the circumstances, Nike are just keen on growing their association. Examination of business points: Additionally Tesco’s principle objective is to take over Homebase and Argos in deals of homeware, electrical merchandise and enterprises, this demonstrates Tesco doesn’t need to just be known as a food retailer association, however they likewise need to be known as an association which additionally offers their clients serious costs in homeware, and electrical products and ventures. Tesco and Nike have various points on the grounds that they’re in various classes of business, in addition they are likewise in an alternate segment of business and proprietorship. Tesco attempt to satisfy the necessities of their clients, they do this by giving their clients items which are of acceptable quality. Tesco’s fundamental intend to improve the well known items that are among their clients that they as of now have; from there on they ought to acquire more items that their clients are needing. Moreover, in present time Tesco are attempting to advance their organization in the electronic, gaming and attire division at a moderate expense. So accordingly despite the fact that its just of a minority Tesco likewise happen to cover some different areas, for example, apparel, gaming and electronic. Tesco will pick points that suit them and are sensible at the end of the day points that can be accomplished. Tesco recognize that reality that other marked items will be costly to purchase and won't suit the organization as so as to make incredible benefits the costs of the items must be sold extravagantly, subsequently so as to sift through this issue Tesco have made their own image of high caliber of items at a low and sensible cost, consequently Tesco has the title of being perhaps the least expensive grocery store in Britain. Anyway different general stores, for example, Asda and Sainsbury’s additionally have their own marked items. Tesco groups an extraordinary quality that all organizations pine for to gangs; and that quality is as a matter of fact the way that Tesco is fantastically composed. I know beyond all doubt that Tesco are sorted out, in light of the fact that I went to Tesco and I saw the way that items that are pertinent are in a similar segment so it makes simpler for the clients to locate their ideal item and contrast the costs and comparative items for instance they find child items in a similar area close to one another, with the goal that guardians hoping to purchase infant grain and infant yogurt won't endure the weariness of venturing out to the opposite finish of the market. Tesco additionally name the areas so clients don’t get befuddled. What I additionally like about Tesco is that they find infant stuff in segments that are close to one another so by and by the client doesn’t need to stroll across to the opposite side of the grocery store to get an oat and the opposite side to get spoils. Anyway other general store that I’ve witnesses for myself, for example, Asda additionally do this. I state that Tesco and Asda are the most sorted out general store in Britain ( Judging from my own eyes), Both markets have new/items with extraordinary proposals close to the passage; they utilize this technique to ensure that new/items with exceptional offers is the main thing that the clients sees, thus the client won't miss the unique offer or another item. Another motivation behind why they do this is on the grounds that Tesco recognizes the way that clients like to see what’s new and that on the off chance that they can’t locate the new roduct/s then they will begin to ask the staff, this will make them occupied and furthermore prevent the staff from focusing on their work. Nike is an organization that sells and assembling all kind of sports wear and items. The favorable circumstances that Nike has are that the two of them assembling and sell items that their clients have an enthusiasm for. With the goal for Nike to sell more products and ventures they (Nike) supp ort sport stars, for example, Cristiano Ronaldo, Roger Federer and Tiger Woods. You can see that these game stars are truly outstanding and on top in their calling, henceforth they have a major fan base and these fans like to emulate their deities and wear comparative dress; because of the reality these games stars groups a tremendous fan base is significant in light of the fact that it will imply that the fans will purchase the Nike items, that the games stars are wearing. Anyway this doesn’t come in modest, as the games stars get paid a gigantic sum for wearing the Nike garments extend. The followings is how much each Sport star get paid by Nike. †¢ Cristiano Ronaldo †Currently gets ? 6 million every year sponsorship. †¢ Roger Federer †Currently gets ? 8. 4607875 million every year sponsorship †¢ Tiger Woods †Currently gets ? 13. 0165962 million per year sponsorship Although these Sports stars get paid liberally, I anyway believe that they are justified, despite all the trouble ‘because they have helped Nike to produce deals. Anyway Adidas who are Nike’s rivalry additionally have support bargains for Sport begins most prominently David Beckham. Anyway my different business (Tesco) won't have the option to support sports stars as their fundamental strength is by selling food items particularly staple goods and game stars are not applicable to what they sell in this way the game stars w

On the Translation of English Idioms Essay

Language and culture are firmly associated and indistinguishable, as a language figure of speech is the pith of the affidavit of the captivating history and culture. Due to geology, history, religion, customs and different parts of life contrasts among Chinese and English Idioms conveying attributes of the various societies and social data, so English-Chinese Idioms regularly experience numerous troubles. From the geological condition, chronicled foundation, customs and strict convictions depicted four parts of social contrasts among Britain and China on the effect of the arrangement of their particular colloquialisms, and point by point portrayal of English Idioms interpretation to manage this social distinction in a few normally utilized interpretation . Watchwords: language; culture; social contrasts; Idioms Translation 1, English figures of speech and social contrasts reflected in the (A)ñž The environment The common habitat is mankind’s endurance and the reason for the improvement of various regular habitat of the arrangement and advancement of national culture have various impacts. Chinese individuals living in the huge region of rich mainland of East Asia, China since antiquated occasions is a huge agrarian nation, the land in people’s lives is crucial. Thusly, there is an impressive segment of Chinese agribusiness and land-related expressions. For example, ‘good weather†dead end†extermination†big spenders’, etc. England is an island encircled by water. Oceanic history, have been living in a world head, so in English and will have a ton of water, fish, and marine-related expression. For example, feeble as water (delicate), drink like a fish (alcohol), to miss the vessel (botched chances), all adrift (a misfortune). In the Chinese social environment, the ‘wind’ that is ‘spring wind’, in the mid year heat frequently connected with the Ku Shu, ‘scorch like fire’, ‘Jiaoyangsihuo’ is regularly used to portray the late spring term . The United Kingdom is situated in the western side of the equator north mild zone, is a marine atmosphere, the report is that the message of spring westerly, the British writer Shelley’s ‘West Wind Song’ (tribute toward the west wi nd) is the correct spring Acura. England’s summer season is warm and lovely, frequently with ‘lovely’, ‘moderate’, ‘OK’ associated. Shakespeare in his poems in one contrasted with the late spring of affection, Shall I contrast thee with asummer’s day? Thou are all the more flawless and progressively mild. (B) The authentic reference From a specific perspective that language is a nation’s social memory and precipitation, the enormous number of Chinese colloquialisms depend on the nation’s history, economy, culture, customs, propensities, shaped the premise, with a solid national social attributes of and broad social and authentic starting points, regularly can not be comprehended from the strict importance and interpretation. For example, ‘mere copycat’, ‘Minglasunshan’, ‘lose the spouse of another warrior off†Three Stooges, the main one wise’, etc. English figures of speech sayings originate from the ‘Bible’ and the Greek and Roman folklore, yet additionally have their particular substance, for example, Achilles’heel (the main lethal shortcoming), meetone’s waterloo (endured a devastating destruction), a Pandora’s box (Pandora’s box), the Trojanhorse (Trojan pony from Greek folklore), bolt of Cupid ( , from Roman folklore). (C) The distinction between training In customary Chinese culture, the mythical beast is an image of propitious creatures. In primitive society, magnificent mythical beast is an image, authority and tastefulness. Subsequently, in Chinese and monster related expressions for the most part contain praise. For example, ‘Dragon and Phoenix Succeed†Ã¢â‚¬ Chenglongkuaixu’, etc. Be that as it may, fantasies and legends of the West, mythical serpent wings, it is a long, textured body, hauling a long tail, fire-breathing from the mouth of creatures, it is alarming. In this way, as Long as the lethal devastation Westerners thing, to be wiped out. Moreover, the pooch in Chinese is an unassuming creature. Chinese sayings with hound related generally harsh: ‘Fox Peng Dog Party’, ‘Goujitiaoqiang’, ‘a dog’s mouth spit no ivory’, etc, while in the Western English-talking nations, hounds are considered man’s most steadfast companion . English figure of speech notwithstanding the dog’s part because of the effect of different dialects, which incorporates an injurious sense, the greater part of them are not intended to be disparaging. Colloquialisms in English, frequently with the dog’s picture to portray human conduct. On the off chance that Youare a serendipitous son of a gun (you are one fortunate), Every canine has his day (mortal Jieyou pleased days). Interestingly, the Chinese individuals are exceptionally cherished felines, with the ‘Chan Mao’ allegory man voracious, regularly close parts, while in Western culture, ‘cat’ is utilized to analogy ‘a malignant woman’. (Iv) strict convictions. Each country has its own strict convictions and strict culture, its people’s qualities and way of life of the development and language have an unpretentious effect. In the long history of a few thousand years, the Chinese country is overwhelmingly Buddhist and Taoist. In this way, there are numerous Chinese Buddhism, Taoism-related figures of speech, for example, ‘Jiehuaxianfo †Road†Bearing at the top of the priority list that’, etc. Furthermore, the Chinese individuals despite everything venerate divine beings, for example, ‘right and proper†thank God†Heaven consistently leaves individuals a way out’, etc. Chinese heads likewise guarantee to be ‘true children of the dragon’. In the United Kingdom and other Western nations, the best effect of religion is Christianity. In the Western brain, God has an incomparable extraordinary force. There are additionally various English sayings with the God-related figures of speech. On the off chance that God enables the individuals who to support themselves (God enables the individuals who to enable themselves), To man proposes, God arranges (Man proposes, God arranges days). Revile an individual is regularly said that God damn you, peril frequently said after the Thank God, or God favor you. Christian precept ‘Bible’ has been viewed as a great of Western culture. Numerous English phrases is absolutely a result of this. For example, the finger on the divider (composing on the divider), provide reason to feel ambiguous about one’s bread the waters (truly do great, without requesting anything). From the above viewpoints, we can see the effect of culture on expression broad and broad. To accurately comprehend the English language students and fruitful lead of Idioms interpretation, we should first English-Chinese have a profound comprehension of the two societies. Second, the primary technique Idioms Translation is the change between the two dialects, while the cozy connection among language and culture transformation demand must be in the language of social transformation. Taking into account this, the interpreter can not be actually strict interpretation, we should better comprehend the way of life behind the exacting data, utilizing the first comprehension of the first language and social information to their own understanding, in light of in another dialect, for example, that of the objective language for the sorts of change, for the peruser to pass the first interpretation precise data, press ‘functional equivalence’ standard so that ‘the peruser to mirror the same’. In this manner, the maxims deciphered the one hand, beyond what many would consider possible with the first significance of ‘the generally fitting, the most normal propagation of such words come out’, with Nida’s words, that is, ‘The best interpretation does no t sound like a translation’; the other On the one hand, yet additionally bend over backward to show the first social data on the interpretation perusers to comprehend the social data contained in the first. Primary techniques are: reposted somewhere else in the paper for nothing Download Center http://www. hi138. com (A) Literal Translation. The purported exacting interpretation technique, isn't against the objective language standards, and Lenovo are not under the conditions that made the blunder in the interpretation hold the first phrase allegory, picture and national, neighborhood highlights approach. It applies somewhat because of the utilization of a wide number of a greater amount of its exacting importance and allegorical significance has been broadly acknowledged by the peruser for the interpretation phrases. On the off chance that a gentleman’s understanding (a gentleman’s understanding); equipped with every kind of weaponry (equipped with every kind of weaponry); to angle in pained water (fish in upset waters); paper tiger (paper tiger); (attract water a bamboo bin). Exacting interpretation of the benefit of having the option to hold progressively finish picture of the first maxim similitude, ethnic style, shading and language. Be that as it may, if the mediator to an extreme or too strict interpretation appropriately, it’s simple to cause the peruser to feel entertaining or crazy, even offer ascent to misconception or mistake affiliation. For example, (Until everything is finished, desire never bites the dust. ), The Pig erroneously charge the Chinese (To put fault on one’s casualty.) ‘Yellow’ and ‘The Pig’ and different words have an undeniable social attributes, if the exacting interpretation, remote perusers won't get why, just to ‘functional equivalence’ approach mediator to perusers in the East and the West has caused and is eager to coordinate emotions. (B) exacting clarification France In request to save the social data contained in the first, it is more utilization of strict, as opposed to summarize, but since of language established in the social soil is unique in relation to exacting interpretation is probably going to be uncertain and unclear. For this situation, just related to fitting comment so as to pass the first content of social information

An Answer to the Question I Proposed at the Beginning of This Article

An Answer to the Question I Proposed at the Beginning of This ArticleSubject area essay topics and sample essays should be the foundation of a solid composition, but it's a mistake to think that just because they include lots of specific information about that subject, that you have the answer to the question at hand. Subject area essays are the meat and potatoes of the composition. Any successful essay has both strong points and weak points.Given that fact, you may think that the topic and sample essays in subject area essay samples do nothing more than supply you with the answers you need. In the wrong hands, though, they can have a rather depressing effect on a student's ability to solve the problem they are addressing. So what is the answer to the question I posed at the beginning of this article?In my opinion, subject area essay samples offer a unique opportunity for those writers who have not yet mastered the art of writing a fine essay. You don't have to write a topic or a sam ple essay. But if you can master the mechanics of topic and sample essays, then you can use them to compose the finest compositions you can imagine.Subject areas are designed to use words as your guide for helping you organize and structure the topic and the surrounding material that is to be the core of your essay. So the better the writer, the better the subject area essay samples will help them. In a sense, writing samples can act as an instructor for students who wish to learn the proper way to construct their subject.Also, writing samples are filled with examples. The ones in subject area essay samples are filled with ideas, sentences, paragraphs, all intended to show you how a writer should construct their own writing. In other words, if you learn how to build a great topic and give yourself the opportunity to provide adequate writing samples, then you are already one step ahead of where most students are. (But remember, writing samples are only one piece of the composition pu zzle.)The ability to write a great topic is one thing, but it is next to impossible to write a great subject from scratch. However, if you can employ the same ability in creating the appropriate topics and sample essays, then you can surely create a topic that will present to you an interesting puzzle that you will be able to solve on your own.In addition, subject area essay samples offer numerous choices for topics. Because the examples are plentiful, you should be able to use these to hone your writing skills without having to worry about finding the exact topic for your next essay.There are thousands of topic and sample essays available on the Internet and in subject area essay samples. The good news is that there are countless examples to choose from. In fact, it is so easy to access and it is so easy to manipulate that it should not be difficult to find topics that present new insights into a subject, or to construct sentences and paragraphs that will add to your understanding of that subject.

2012 One-year Top Performing Direct Plans Q1

Savingforcollege.com ranks the performance of direct-sold 529 plans. Direct-sold plans are those that consumers can enroll in without using a broker. We have prepared one-year, three-year and five-year performance tables. To prepare this ranking, we compared a subset of portfolios from each 529 savings plan. We selected portfolios based on their mix of stocks, bonds and money market funds, which allows for an apples-to-apples comparison in seven asset-allocation categories. The lower the "percentile," the better the ranking. This ranking could be a useful tool for you when selecting which direct 529 plan might be right for you. Here are our 529 performance rankings as of March 31, 2012 for Direct-sold 529 plans. One-year performance ranking (click here for three-year performance table and five-year performance table): Rank State Plan Percentile 1 New York New York's 529 College Savings Program -- Direct Plan 23.61 2 Pennsylvania Pennsylvania 529 Investment Plan 25.08 3 Utah Utah Educational Savings Plan (UESP) Trust 26.11 4 Michigan Michigan Education Savings Program 27.14 5 Illinois Bright Start College Savings Program -- Direct-sold Plan 29.10 6 Iowa College Savings Iowa 30.22 7 Vermont Vermont Higher Education Investment Plan 31.46 8 New Mexico The Education Plan's College Savings Program (Direct-sold) 31.49 9 Oklahoma Oklahoma College Savings Plan 32.38 10 Georgia Path2College 529 Plan 32.86 11 Minnesota Minnesota College Savings Plan 32.99 12 Colorado Direct Portfolio College Savings Plan 33.89 13 Hawaii Hawaii's College Savings Program 34.30 14 Kentucky Kentucky Education Savings Plan Trust 34.31 15 Alabama College Counts 529 Fund (Direct-sold) 34.58 16 District of Columbia DC 529 College Savings Program (Direct-sold) 34.72 17 Nevada The Vanguard 529 Savings Plan 38.19 18 Alaska University of Alaska College Savings Plan 38.50 19 Oregon Oregon College Savings Plan 39.52 20 Missouri MOST - Missouri's 529 College Savings Plan (Direct-sold) 40.26 21 Alaska T. Rowe Price College Savings Plan 40.38 22 Indiana CollegeChoice 529 Investment Plan (Direct-sold) 41.25 23 Kansas Learning Quest 529 Education Savings Program (Direct-sold) 41.83 24 Texas Texas College Savings Plan 42.08 25 Maine NextGen College Investing Plan -- Client Direct Series 42.14 26 North Dakota College SAVE 45.61 27 Wisconsin EdVest (Direct-sold) 46.37 28 Arkansas GIFT College Investing Plan 48.74 29 Idaho Idaho College Savings Program (IDeal) 49.34 30 Maryland College Savings Plans of Maryland -- College Investment Plan 49.58 31 Ohio Ohio CollegeAdvantage 529 Savings Plan 49.64 32 South Carolina Future Scholar 529 College Savings Plan (Direct-sold) 50.49 33 Nebraska Nebraska Education Savings Trust - Direct College Savings Plan 54.23 34 Nebraska TD Ameritrade 529 College Savings Plan 56.68 35 Connecticut Connecticut Higher Education Trust (CHET) 57.12 36 Virginia Virginia Education Savings Trust (VEST) 57.15 37 West Virginia SMART529 WV Direct 58.31 38 Louisiana START Saving Program 62.92 39 Kansas Schwab 529 College Savings Plan 63.18 40 Massachusetts U.Fund College Investing Plan 63.22 41 Arizona Fidelity Arizona College Savings Plan 63.39 42 Delaware Delaware College Investment Plan 63.41 43 New Hampshire UNIQUE College Investing Plan 63.55 44 New Jersey NJBEST 529 College Savings Plan 64.18 45 Rhode Island CollegeBoundfund (Direct-sold, Alternative RI) 66.42 46 South Dakota CollegeAccess 529 (Direct-sold) 70.57 47 Nevada USAA 529 College Savings Plan 73.17 48 Montana Montana Family Education Savings Program Investment Plan 76.26 49 West Virginia SMART529 Select 79.50 - California The ScholarShare College Savings Plan NA - Florida Florida College Investment Plan NA - Mississippi Mississippi Affordable College Savings (MACS) Program NA - Nevada SSgA Upromise College Fund NA - North Carolina National College Savings Program NA NA = Not Applicable = Program does not have at least one portfolio with sufficiently-long performance in a minimum of four asset allocation categories under our ranking model. The Savingforcollege.com plan composite rankings are derived using the plans' relevant portfolio performance in seven unique asset allocation categories. The asset-allocation categories used are: 100 percent equity, 80 percent equity, 60 percent equity, 40 percent equity, 20 percent equity, 100 percent fixed and 100 percent short term. The plan composite ranking is determined by the average of its percentile ranking in the seven categories. The performance data underlying these rankings represent past performance and are not a guarantee of future performance. Current performance may be lower or higher than the performance data used. A plan portfolio's investment return and principal value will fluctuate so that an investor's shares or units when redeemed may be worth more or less than their original cost. Investors should carefully consider plan investment goals, risks, charges and expenses by obtaining and reading the plan's official program description before investing. Investors should also consider whether their beneficiary's home state offers any tax or other benefits that are available for investments only in such state's 529 plan. Brokers, please note: For internal use only and not for use with or to be shown to the investing public. Disclaimer: JFH Innovative, LLC shall not be liable for any errors or omissions in this report. Users should rely on official program disclosures. For broker-sold plan rankings, click here. Savingforcollege.com ranks the performance of direct-sold 529 plans. Direct-sold plans are those that consumers can enroll in without using a broker. We have prepared one-year, three-year and five-year performance tables. To prepare this ranking, we compared a subset of portfolios from each 529 savings plan. We selected portfolios based on their mix of stocks, bonds and money market funds, which allows for an apples-to-apples comparison in seven asset-allocation categories. The lower the "percentile," the better the ranking. This ranking could be a useful tool for you when selecting which direct 529 plan might be right for you. Here are our 529 performance rankings as of March 31, 2012 for Direct-sold 529 plans. One-year performance ranking (click here for three-year performance table and five-year performance table): Rank State Plan Percentile 1 New York New York's 529 College Savings Program -- Direct Plan 23.61 2 Pennsylvania Pennsylvania 529 Investment Plan 25.08 3 Utah Utah Educational Savings Plan (UESP) Trust 26.11 4 Michigan Michigan Education Savings Program 27.14 5 Illinois Bright Start College Savings Program -- Direct-sold Plan 29.10 6 Iowa College Savings Iowa 30.22 7 Vermont Vermont Higher Education Investment Plan 31.46 8 New Mexico The Education Plan's College Savings Program (Direct-sold) 31.49 9 Oklahoma Oklahoma College Savings Plan 32.38 10 Georgia Path2College 529 Plan 32.86 11 Minnesota Minnesota College Savings Plan 32.99 12 Colorado Direct Portfolio College Savings Plan 33.89 13 Hawaii Hawaii's College Savings Program 34.30 14 Kentucky Kentucky Education Savings Plan Trust 34.31 15 Alabama College Counts 529 Fund (Direct-sold) 34.58 16 District of Columbia DC 529 College Savings Program (Direct-sold) 34.72 17 Nevada The Vanguard 529 Savings Plan 38.19 18 Alaska University of Alaska College Savings Plan 38.50 19 Oregon Oregon College Savings Plan 39.52 20 Missouri MOST - Missouri's 529 College Savings Plan (Direct-sold) 40.26 21 Alaska T. Rowe Price College Savings Plan 40.38 22 Indiana CollegeChoice 529 Investment Plan (Direct-sold) 41.25 23 Kansas Learning Quest 529 Education Savings Program (Direct-sold) 41.83 24 Texas Texas College Savings Plan 42.08 25 Maine NextGen College Investing Plan -- Client Direct Series 42.14 26 North Dakota College SAVE 45.61 27 Wisconsin EdVest (Direct-sold) 46.37 28 Arkansas GIFT College Investing Plan 48.74 29 Idaho Idaho College Savings Program (IDeal) 49.34 30 Maryland College Savings Plans of Maryland -- College Investment Plan 49.58 31 Ohio Ohio CollegeAdvantage 529 Savings Plan 49.64 32 South Carolina Future Scholar 529 College Savings Plan (Direct-sold) 50.49 33 Nebraska Nebraska Education Savings Trust - Direct College Savings Plan 54.23 34 Nebraska TD Ameritrade 529 College Savings Plan 56.68 35 Connecticut Connecticut Higher Education Trust (CHET) 57.12 36 Virginia Virginia Education Savings Trust (VEST) 57.15 37 West Virginia SMART529 WV Direct 58.31 38 Louisiana START Saving Program 62.92 39 Kansas Schwab 529 College Savings Plan 63.18 40 Massachusetts U.Fund College Investing Plan 63.22 41 Arizona Fidelity Arizona College Savings Plan 63.39 42 Delaware Delaware College Investment Plan 63.41 43 New Hampshire UNIQUE College Investing Plan 63.55 44 New Jersey NJBEST 529 College Savings Plan 64.18 45 Rhode Island CollegeBoundfund (Direct-sold, Alternative RI) 66.42 46 South Dakota CollegeAccess 529 (Direct-sold) 70.57 47 Nevada USAA 529 College Savings Plan 73.17 48 Montana Montana Family Education Savings Program Investment Plan 76.26 49 West Virginia SMART529 Select 79.50 - California The ScholarShare College Savings Plan NA - Florida Florida College Investment Plan NA - Mississippi Mississippi Affordable College Savings (MACS) Program NA - Nevada SSgA Upromise College Fund NA - North Carolina National College Savings Program NA NA = Not Applicable = Program does not have at least one portfolio with sufficiently-long performance in a minimum of four asset allocation categories under our ranking model. The Savingforcollege.com plan composite rankings are derived using the plans' relevant portfolio performance in seven unique asset allocation categories. The asset-allocation categories used are: 100 percent equity, 80 percent equity, 60 percent equity, 40 percent equity, 20 percent equity, 100 percent fixed and 100 percent short term. The plan composite ranking is determined by the average of its percentile ranking in the seven categories. The performance data underlying these rankings represent past performance and are not a guarantee of future performance. Current performance may be lower or higher than the performance data used. A plan portfolio's investment return and principal value will fluctuate so that an investor's shares or units when redeemed may be worth more or less than their original cost. Investors should carefully consider plan investment goals, risks, charges and expenses by obtaining and reading the plan's official program description before investing. Investors should also consider whether their beneficiary's home state offers any tax or other benefits that are available for investments only in such state's 529 plan. Brokers, please note: For internal use only and not for use with or to be shown to the investing public. Disclaimer: JFH Innovative, LLC shall not be liable for any errors or omissions in this report. Users should rely on official program disclosures. For broker-sold plan rankings, click here.

High Power Continuous Wave Fiber Laser System - Free Essay Example

Sample details Pages: 13 Words: 3964 Downloads: 5 Date added: 2017/06/26 Category Statistics Essay Did you like this example? Introduction of High Power Fiber Laser The optical fiber with very high surface-to-volume ratio and a strong waveguide effect provides the fiber based laser source the potential to generate high power laser beam with high quality. In addition to the capacity of generating raw optical power with high beam quality, the fiber laser system has other appealing features, such as supporting robust and compact system designs, allowing ultrashort pulse operation, offering a board wavelength tunability, and providing high gains. Those features stimulate the research on the high power fiber lasers system, and lay the foundation of novel appealing applications, such as remote material processing, aerospace and defense. Don’t waste time! Our writers will create an original "High Power Continuous Wave Fiber Laser System" essay for you Create order In the past decade, a remarkable increase of the powers produced by fiber lasers with high beam quality has been achieved (see Fig.1). As a result, the high power laser becomes strong counterpart of the solid-state bulk laser, and penetrates rapidly into areas that formerly other lasers were used. Fig. 1. Progress in output power from diffraction-limited and near-diffraction-limited Yb-doped fibers . Literature Review In the early 1960s, the first fiber laser was demonstrated by Snitzer . The doped fiberà ¢Ã¢â€š ¬Ã¢â€ž ¢s potential for high optical gain was revealed by David Payne and co-researchersà ¢Ã¢â€š ¬Ã¢â€ž ¢ working on Neodymium- doped fibers in mid 1980s . In 2009, the high power fiber laser, which based on a specifically silica-host ytterbium-doped fiber-based laser (YDFL), obtained 10 kW output in the single-mode (SM) regime. Although architectures are different, the high-power fiber lasers and amplifiers are mostly archived with rare-earth-doped (RE-doped) double-clad fibers. The double-clad fiber, which was initially demonstrated in 1988, provided the option of cladding pumping, and proved to be one of the key technologies for power scaling. The structure of this double cladding is that the active RE-doped core is surrounded by a much larger à ¢Ã¢â€š ¬Ã…“inner claddingà ¢Ã¢â€š ¬? (see Fig. 2), and are encircled together by out cladding. The pump beam emitted by fiber-coupled high-power diode bars or other kinds of laser diodes is coupled into the inner cladding, and confined within it by an outer cladding. The confined pump beam will be absorbed into the core while it propagates along the fiber. The laser light is generated in the central core, and the laser light can have very good beam quality à ¢Ã¢â€š ¬Ã¢â‚¬Å" even diffraction limited beam. Thereby, by means of double cladding configurations one realized the conversion from low brightness pump to high brightness single-mode fiber laser output. As the spatial and angular pump acceptance [can be expressed as the product of area and the square of the numerical aperture (NA)] for the inner cladding is significantly improved to the core pump, Such conversion is more effective, and close to 5 orders have been demonstrated experimentally. Among high power RE-doped fiber lasers, the YDFL is notable in term of high power. The Ybà ¢Ã¢â€š ¬Ã¢â€ž ¢s broad absorption band extends from 900 to 980 nm (see fig 3), covering high power pump LDà ¢Ã¢â€š ¬Ã¢â€ž ¢s best performance wavelengths, offers a low quantum defect [energy difference between pump and laser photons] for pumping with 9xx nm LD and lasing above 1040nm. This superior property offers the potential for achieving very high power efficiencies and reducing thermal effects. In addition, lasing at wavelength above 1040nm, the Yd ion shows a simple four à ¢Ã¢â€š ¬Ã¢â‚¬Å"level structure, that excludes excited state absorption and also a variety of detrimental quenching processes allowing high doping concentrations, which means high pump absorption per unit length. On the contrary, the small quantum defect also has a usually unwanted consequence: the significant quasi-three-level behavior, especially when lasing at short wavelengths (less then 1040nm), that will cause a high threshold and decrease the power efficiency. Fig. 2. Structure of a double-clad fiber and principle of cladding-pumping The Nd doped laser emitting at 1060 nm is a four-level system, which means a lower laser threshold. Associated with the relatively advanced state of 808 nm diodes for pumping Nd:YAG, this made Nd the choice for high power fiber lasers in early stage. Todayà ¢Ã¢â€š ¬Ã¢â€ž ¢s high power pump diodes in 9 xx nm are sufficiently bright to make threshold unimportant for most quasi-three-level high power fiber lasers. These overcome the obstacle of ytterbiumà ¢Ã¢â€š ¬Ã¢â€ž ¢s higher threshold and raise advantages of a lower quantum defect and higher doping concentration with quench-free. The first single-mode Yb doped fiber laser with output power over 100 W was demonstrated in 1999 , and it illustrated that the advantages of Yb doped double cladding structure can support for further increase in the average power by scaling the size of the optical fiber and the power of pump diode source. Soon after that, the power of cladding pumped YDFL obtained the kilowatt level. Thereafter, by invest igating the large-area core design and fabrication, the single-mode operation in kilowatt level was realized that would not have been possible for Nd doping. Figure 3: Absorption and emission cross sections of ytterbium-doped germanosilicate glass, as used in the cores of ytterbium-doped fibers. Another sophisticated technique which is adopted in all double-clad fiber lasers at 3 kW and above, is tandem-pump [in-band pumping with high-brightness pump sources, such as one or several fiber lasers, or thin disk laser]. The tandem pump makes it possible to pump close to the emission wavelength so that the quantum defect heating will be low resulting in a reduced thermal load. Actually, some advanced solid-state lasers, such as thin disk laser, is well matched with requirements of in-band high brightness pumping source, and 1 KW level output thin disk laser pumped fiber laser have been realized. Nonlinearities are an issue to further increase the CW output power of the fiber laser. The fiber laser considered above such as in Fig. 1 has operated with linewidths in the 1à ¢Ã¢â€š ¬Ã¢â‚¬Å"10 nm range. In such system with cw operating, excepting at the extremely high powers or long delivery fibers, the stimulated Raman scattering (SRS) is a weak effect and is relatively easy to prevent. However, for output power above 10 kW, the Raman gain can become so high (tens of decibels) that a considerable part of the power is transferred to a longer-wavelength Stokes wave, reducing the power in the signal wavelength. There are some applications need single frequency sources which can provide light power with narrower spectral line width, such as coherent beam combination of multiple single frequency fiber sources with high power. This scheme offers a promising method for further power scaling, and consequently this stimulates interest in single-frequency power scaling. For narrow bandwid th, especially at linewidths less than 10 MHz, the SBS is the dominate nonlinearity and the severe obstacle for high power single-frequency fiber sources. The SBS can be suppressed with shorter fiber and larger mode field area, and output power of hundred watts has been reported with such schemes .However, this power is still less comparing with the bulk solid state laser. There are several options for SBS mitigation, including straining the fiber in order to broaden the SBS gain bandwidth, and reducing overlap between the optical and acoustic fields. The highest power high-gain fiber amplifier can archive 1.7KW. It was realized by combination of the modest spectral broadening with phase modulation and the fiber with enlarged effective mode area. The most effective way to mitigate nonlinearities (excluding self-focusing) is to enlarge the effective mode area by optimizing geometry designs and material choices of fiber structure. Unlike the passive power delivery fiber, this task is more challenge for active fiber, as doping-induced refractive index changing, and thermal stability will be issues. A straightforward design approach to maintain pure single-mode operation is to increase the core diameter, with the NA reducing correspondingly. However, the downside is the waveguide effect gets weaker, and consequently light is easier lost from the core when the fiber is bent. More works on fiber designs for addressing these challenges are related to photonic crystal fibers techniques. It is possible to make single mode operation in a multi-mode supported fiber, by building up preferentially amplify, or attenuate for specific mode, while the mixing or coupling between modes should be controlled to minimum. There have been works focu sed on using differential gain by selective RE doping across the core , and differential-bend-loss by controlled bending of the fiber. The leakage channel and chirally coupled core fibers are designed to selectively couple propagation mode to high loss mode. The high order mode but not the fundamental mode is coupled to leaky mode, which will substantially be attenuated. The multifilament core and multicore fiber arrange filaments or cores in a two-dimensional array. There are evanescent-field coupling among cores, and the overall structure can exhibit single-mode guidance with large mode area. Academic Objectives From the aspect of power generation, Investigation of advanced fiber for mitigating nonlinearity will be still the most critical issue in increasing the output power for cw fiber lasers. It has been estimated that the maximum single core output powers of the ytterbium doped fiber laser should be at several tens of kilowatts level based on present technique. However, single-mode operation is not indispensable for lots of high power lasers applications. The single or near single mode operation in the MM fiber which is developed by balancing the mode quality, the achievable power, and the damage threshold of the fiber, can offer possibilities to archive higher output power. In addition to that, as the emission wavelength of well developed thin disk laser is still covered by the Yb ionà ¢Ã¢â€š ¬Ã¢â€ž ¢s absorption band and is more close to the emission band of the Yb ion, the research on novel architecture using thin disk laser to tandem pump the special designed Yb doped fiber laser al so offers the potential to increase output power of fiber laser and develop novel fiber laser with useful function. The proposed research will focus on advanced fiber, especially for the evanescent-field coupled waveguides, also called multi-core fibers (MCF). The main aim is to design and realize novel types of active MCF for increasing the output power of fiber laser with good beam quality, and for suppressing the SBS effect. Besides that, Based on the advanced thin-disk laser, and the novel MCF fiber, the investigation on the novel laser architectures will also be performed. The Outline of the Project According to the above proposed objectives, the research work can be divided to two main phases. The first phase will be focused on fiber design and fabrication, and the expected deliverable is the novel active fiber with improved performance in nonlinearity mitigation and bending resistant. The other phase is about the novel fiber laser architecture, and investigation of the novel tandem pump configuration based on thin-disk laser will be performed. Mathematical Model and Design Strategy The main nonlinearities for cw operating fiber laser is SRS and SBS. Although both of them can be mitigated by the enlarged mode area, the SBS is still too strong for increasing the power of single frequency laser in the LMA fiber. The proposed research aimed to suppress the SBS in the LMA fiber for mitigating both SRS and SBS. According to the previous research, the SBS threshold can be expressed by : (1) The ÃŽÂ ±u is acoustic attenuation coefficient for the acoustic mode of order u, Aeff is the optical effective mode area, G(Ñ ´max) is the SBS effective gain coefficient at the peak frequency, K is the polarization factor. We can see form the equation. Beside the mode area, the SBS can be suppressed by increasing the acoustic loss, reducing the overlap integral, and the SBS effective gain coefficient. The is the normalized overlap integral of the electric and acoustic fields and it can be expressed as : (2) The E0 is the optical field associated with the fundamental mode, and à ?u the field of a longitudinal acoustic eigen-mode of order u. The overlap integral can be changed by modifying the fiber refractive index profile and acoustic velocity profile. The acoustic loss can be changed by glass composition design. As different dopants have different effects on optical and acoustic properties, it is possible to create suitable dopants profile in the core and cladding to reducing the overlap integral or increasing the acoustic loss. Table 1 is some common dopants used for making silica glass based fibers. The profile of the optical and acoustic field can be indicated by optical and acoustic refractive indices. Similar to the optical refractive index, acoustic refractive index is defined as na(r) = VL Silica /VL (r) , where VL(r) is the longitudinal acoustic velocity in the core, and VL Silica is the longitudinal acoustic velocity of pure silica glass. Table 1. Trend of optical and acoustic refractive index change of different dopants in silica GeO2 P2O3 TiO2 B2O3 F2 Al2O3 Optical refractive index à ¢Ã¢â‚¬  Ã¢â‚¬Ëœ à ¢Ã¢â‚¬  Ã¢â‚¬Ëœ à ¢Ã¢â‚¬  Ã¢â‚¬Ëœ à ¢Ã¢â‚¬  Ã¢â‚¬Å" à ¢Ã¢â‚¬  Ã¢â‚¬Å" à ¢Ã¢â‚¬  Ã¢â‚¬Ëœ Acoustic refractive index à ¢Ã¢â‚¬  Ã¢â‚¬Ëœ à ¢Ã¢â‚¬  Ã¢â‚¬Ëœ à ¢Ã¢â‚¬  Ã¢â‚¬Ëœ à ¢Ã¢â‚¬  Ã¢â‚¬Ëœ à ¢Ã¢â‚¬  Ã¢â‚¬Ëœ à ¢Ã¢â‚¬  Ã¢â‚¬Å" One straightforward approach to modify the loss for optical and acoustic field of a fiber structure is created a type of optical guiding and acoustic anti-guides with a dopant material(Fig 4 (a)), such as Al2O3, and it has been demonstrated in . The other approach is to reduce optical and acoustic field overlap, with different dopants in the core (Fig 4 (b)). The resultant optical and acoustic refractive index profiles of above approaches are shown below. (b) Fig. 4. Dopant designs for reducing the overlap of the optical and acoustic fields The strategies shown in fig 4 are based on single core fiber. There are quite a few research works on improving the effective mode field in single core fiber, and it is little room to enlarge the effective mode field areas further without detrimental effect in single core fiber LMA. Recently, multicore fiber based LMA has been investigated as passive delivery fiber , and as active fiber in the novel laser architecture. The supported optical mode field of MCF can be designed by core size and core interval; the profile of the acoustic and optical field can be modified by the distribution of dopants and doping area size; and the loss of the optical and acoustic can be controlled by doping material. Thus, it is worth investigating a novel active MCF supporting a few modes or only single supermode with the reduced overlap between the acoustic and optical field. Optical Index Al Yb Ge F/B Acoustic Index Fig 5 the schematic of the proposed 19 core double cladding fiber A fiber design strategy to suppress the SBS is shown in Fig 5. An optical guide while acts as an acoustic anti-guide in the effective optical field areas of MCF will be fabricated by manipulating dopants in core and cladding, for example as shown in fig 5, by choosing Al2O3 in core and GeO2 in cladding. Because the fields of optical and acoustic are separated, the interaction between the optical and acoustic waves is weaker. Furthermore, the MCF will be designed to support a few modes or only one supermode, that benefits for manipulating refraction index to increase threshold of the SBS in the single mode MCF, as the à ¢Ã‹â€ Ã¢â‚¬  n=neffà ¢Ã‹â€ nclad of single mode MCF is larger than single mode single core fiber(SMF), for example, the index difference à ¢Ã‹â€ Ã¢â‚¬  n=neffà ¢Ã‹â€ nclad is 3.69ÃÆ'—10à ¢Ã‹â€ 4 in the case of the 19-core fiber reported in and only 1.60ÃÆ'—10à ¢Ã‹â€ 4 for the SMF, providing more room of à ¢Ã‹â€ Ã¢â‚¬  n for manipulating dopants. Finally, the reference value of parameters such as the diameter of each core, the core interval, and the doped areas of each core, will be archived by numerical calculation. Numerical Calculation The optical field in the waveguide can be solved by numerical calculation the Maxwell equations. Like the optical field, by numerical calculating the nonlinear acoustic equation, the acoustic field can be obtained. After that the SBS threshold can be calculated with equation (1), (2). From the nonlinear acoustic equation, we can obtain the equation that determines the longitudinal acoustic eigen-modes. The acoustic modes that contribute to the SBS associated with the optical fundamental mode have constant azimuth. Neglecting the damping factor, the radial distribution of such a mode can be expressed as: (3) The ÃŽÂ ©u is the acoustic frequency and the ÃŽÂ ²u is the propagation constant of the acoustic mode, VL(r) is the longitudinal acoustic velocity profile across the fiber. The wave equation for optical field in waveguide is derived from the general Maxwell and can be written as: (4) The EO is the optical field, ko=2p/l is the wave number of the optical field, and no(r) is the refraction index profile across the fiber. The optical mode is efficiently backscattered by the acoustic mode when the phase-match condition, ÃŽÂ ² = 2ÃŽÂ ²u, is fulfilled, where ÃŽÂ ² is the propagation constant of the optical field. The ÃŽÂ ² is determined by the optical wavelength ÃŽÂ », the effective refractive index no,eff, and it can be expressed as: ÃŽÂ ² =kono,eff=2pno,eff/l. Determined by the structure, the acoustic field in the proposed 19 core fiber is confined in the inter cladding, and the acoustic index can affect the confining effect. As the position of inter cladding is fixed, once the doping concentration is chosen, the acoustic field will be determined. The optical field in the MCF is determined by both the doping concentration and the geometry structure of the MCF. It is the geometry structure of the MCF provides the extra room to design the optical field with desired mode. The field of a longitudinal acoustic (à ?u) can be numerical calculated with finite-element method. beside the finite-element method, previous research has indicated the à ?u can be solved by utilizing the solver for optical scalar wave equation after defining a few new terms for acoustic wave. to numerical solve the equations (4), as numerical calculation by the finite element method is still valid when strong coupling exists between the different cores, the mode structure of the optical filed in the MCF is also calculated by finite-element method based on commercial available software such as Fimmwave or Comsol-Multiphysics. After knowing the à ?u and the EO, the can be calculated by taking the à ?u and E0 into equation (2). Finally, taking the into equation (1), the Pth of the designed fiber can be obtained. The theoretical M2 propagation factor can be computed with the method in. For a doping state, different Pth value and mode structures can be achieved for different geometry parameter, such as single core diameter and core interval. Optimizing the geometry parameter is necessary to get the high Pth value with good mode structures. Finally, repeatedly implementing above step for different doping condition, a series of optimized reference parameters can be obtained. The home institute IFSW has equipped the fiber manufacturing facility à ¢Ã¢â€š ¬Ã¢â‚¬Å" consisting of a modified chemical vapor deposition (MCVD) preform production lathe and the new commissioned drawing tower. The prototype of the proposed double-clad MFC fiber will be produced in the IFSW by the stack and draw technique. Investigation on the Laser Architectures The mode field mismatch and high operation power set the obstacles on employing the state of art fiber communication components in the high power laser architecture. Beside that some of critical components for high laser, such Bragg gratings in the LMA cores, large mode area pump coupler or combiner for high power diode are still in the initial stages. Above aspects cause the architecture for the exited high power laser is limited comparing with well developed communication band fiber laser. Most of the previous research on increasing the output power focused on developing the LMA fiber. As the difficulty of increasing the output power by enlarging the mode field is increasing continuously, it is time to consider improve the laser output from other aspect. The high brightness power scalable thin disk laser acting as the in-band pumping source can generate less quantum defect heat than 9ÃÆ'—ÃÆ'—nm laser diode, providing the potential to developing novel or improving existed laser structure by using components which are thermal damage or degradation sensitive. Thus there are rooms to increase the output power or improve the efficiency by developing the laser architecture with thin disk laser and special designed high power components. One of proposed architecture improvements is to replace the butt-coupled HR-mirror in the existed laser with the Bragg grating in the core of the double cladding fiber. Fig 6 (a) the butt-coupling mirror based laser architecture Fig 6 (b) the FBG based laser architecture FBG1,2 reflectors for the laser radiation; FBG3 reflectors for the pump light; The reflection rate of the FBG1 is around 99%, that of FBG2is around 50%. For the butt-coupled mirror based laser architecture (Fig 6 (a)), as the butt-coupled mirror will reflect both the pump light and the laser radiation on a very small area, the energy densities will be extremely high in core and cladding near the conjunct point. To withstand such high power densities, special material substrate such as the sapphire is needed to remove the heat very quickly. Even though, the core power density is still close to the damage threshold of the mirror coating. Furthermore, as the pump wavelength is closed to the laser radiation wavelength, to fabricate the dichroic mirror will be rather difficult. Although the Bragg grating inside the fiber core still has the problem of thermal damage, the damage threshold of FBG will be higher than mirror face. Considerable power increasing is expected for replaying mirror with the Bragg grating. From the aspect of fabrication, the wavelength of the Bragg grating is determined by the mask period and the refraction index of the fiber core, it will be easy to fabricate two FBG with spectrum interval larger than 4nm, which is enough to separate the in band pump light and laser radiation. Finally the FBG also can provide the facility to control the laser wavelength, and the laser output wavelength will be determined by the corresponded reflector. In fig 6 they are FBG1,2. Fig 7 the proposed hybrid laser architecture DMCF: doped multicore double cladding fiber, SMF: single-mode fiber, PMSF: polarization maintained single mode fiber ISO1: polarization dependent optical isolator, Amp: amplifier, DM: dichroic mirror, BS: beam splitter,Li (i = [1; 5]): plus lenses, FBG1: fiber Bragg grating for laser radiation, FBG2: fiber Bragg grating for pump light, PZT: Piezoelectric Ceramics Limited by components, many well developed communication fiber laser techniques such as wavelength tuning and polarization stabilizing cannot be projected to high power fiber laser area directly. A promising method to solve the problem is to develop hybrid architecture which employs a low power single mode fiber feedback loop to control the high power laser. By applying the advanced communication laser techniques in the single mode feedback loop, the high power fiber laser with wavelength tuning and polarization stabilizing can be realized. The proposed hybrid laser architecture with wavelength tuning and polarization stabilizing is shown in fig 7. The thin disk emitted pump light is coupled to the double cladding fiber with a dichroic mirror and a plus lens. The FBG in pump wavelength is employed in the far end of the active fiber. A small part of the emitted beam is reflected and coupled to the feedback loop whereas the most of power is coupled out from the laser cavity. The lens set (L4 to L6) constitutes a free-space imaging system for projecting the far field of the DMCF onto the input face of the SMF. Polarization independent optical isolators and circulator in the feedback loop determined the light traveling direction and eliminated the unwanted reflected light. Furthermore, the polarization independent optical isolator shapes the light to single polarization state, which will be persevered in the feedback loop by polarization maintained fiber. The FBG1 is fixed in a stretch preloaded piezoelectric ceramics, and the reflected wavelength can be tuned slightly by driving the PZT with Bi-directional signal. After passing th e feed pack fiber, the DMCF will amplify the seed laser radiation, and consequently power will be scaled and the polarization can be preserved. The Estimated Time Table Milestones Year 1 Year 2 Year 3 Modelling of the multi core fibre x x x Numerical calculating the parameter of the model x x Fabrication of the multi-core fibre x x Improving the performance of the multi-core fibre x x Improving the performance of the existed architectures x x Investigating the novel laser architectures x x The Bibliography