【摘要】：線偏振激光在激光通信、高精度傳感、二次諧波產(chǎn)生、光學參量振蕩、光束合成等領(lǐng)域有重要的應(yīng)用價值。通常情況下,通過在激光系統(tǒng)中引入在線或空間偏振態(tài)選擇器件可以獲得線偏振激光。但是,引入偏振態(tài)選擇器件存在插入損耗大,系統(tǒng)穩(wěn)定性差,成本高,輸出功率受限等問題。不含有偏振態(tài)選擇器件的線偏振光纖激光器可以有效克服這些缺點,并有利于線偏振光纖激光器的全光纖化。目前,國內(nèi)關(guān)于全光纖結(jié)構(gòu)的高功率線偏振激光器的研究并不多見。本文結(jié)合實驗室現(xiàn)有條件,在不引入偏振態(tài)選擇器件的條件下,基于單一振蕩器或主振蕩功率放大(Master Oscillator Power Amplifier,簡稱MOPA)方案,以實現(xiàn)線偏振激光高功率、高效率、高消光比輸出為目標,從理論和實驗兩個方面對高功率線偏振光纖激光技術(shù)進行了研究。首先,調(diào)研了國內(nèi)外在線偏振光纖激光器方面的研究現(xiàn)狀和進展,分析了四種類型線偏振光纖激光器的實現(xiàn)原理以及各自的特點,確定了適合采用全光纖結(jié)構(gòu)并具備高功率輸出潛力的線偏振振光纖激光器方案。其次,介紹了保偏光柵偏振模選擇基本原理,實現(xiàn)了一臺基于該原理的全光纖線偏振光纖激光振蕩器,實現(xiàn)了42.3 W線偏振激光輸出,消光比優(yōu)于14 dB。對光柵的溫度特性進行了測試和理論分析,實驗研究和分析了光柵溫度和偏振串擾對該線偏振光纖激光器輸出特性的影響,指出了該類型線偏振光纖激光器的特點,提出了提高該類型激光器輸出功率、改善該類型激光器輸出特性的有效途徑。同時,介紹了彎曲損耗偏振模選擇基本原理,對熊貓型保偏光纖的彎曲損耗進行了數(shù)值仿真,實現(xiàn)了一臺基于該原理的全光纖線偏振光纖激光振蕩器,實現(xiàn)了93.2 W線偏振激光輸出,消光比優(yōu)于15.3 dB,這是目前國內(nèi)基于該原理的線偏振光纖激光振蕩器的最高輸出功率。分析了該激光器的輸出特性與彎曲損耗、光柵參數(shù)、光柵溫度和偏振串擾的關(guān)系。對比分析了該類型激光器與基于保偏光柵偏振模選擇原理的線偏振光纖激光振蕩器的差異以及各自的優(yōu)缺點,提出了改善和提升不含偏振態(tài)選擇器件的全光纖線偏振光纖激光器輸出特性的途徑,對獲得更高功率、更高消光比和穩(wěn)定性更好的線偏振激光器具有一定的借鑒和指導意義。進一步,以基于彎曲損耗偏振模選擇原理的線偏振光纖激光振蕩器作為種子激光,采用一級MOPA方案,成功實現(xiàn)了線偏振光纖激光的高功率、高效率、高消光比、近衍射極限輸出,最高輸出功率1491 W,斜效率82.6%,消光比優(yōu)于13.8dB,M2因子約為1.2,這是目前公開報道的線偏振光纖激光的最高輸出功率。同時,采用考慮放大自發(fā)輻射和受激拉曼散射的速率方程模型,分析了該方案進一步提升功率的潛力。
[Abstract]:Linear polarization laser has important application value in the fields of laser communication, high precision sensing, second harmonic generation, optical parametric oscillation, beam synthesis and so on. In general, linear polarization laser can be obtained by introducing on-line or spatial polarization state selection devices into laser system. However, the introduction of polarization selection devices has many problems, such as large insertion loss, poor system stability, high cost and limited output power. Linear polarization fiber lasers without polarization state selection devices can effectively overcome these shortcomings and facilitate the all-fiber conversion of linear polarization fiber lasers. At present, there are few researches on high-power linear polarization laser with all-fiber structure in our country. In this paper, based on the single oscillator or main oscillation power amplifier (MOPA) scheme, the linear polarization laser with high power and high efficiency can be realized based on the existing conditions of the laboratory and without the introduction of the polarizing state selective device (Master Oscillator Power Amplifier,), which is based on the single oscillator or main oscillation power amplifier (MOPA). The technique of high power linear polarization fiber laser is studied both theoretically and experimentally for the purpose of high extinction ratio output. Firstly, the research status and development of on-line polarization fiber lasers at home and abroad are investigated, and the realization principles and characteristics of four types of linear polarization fiber lasers are analyzed. A linear polarization fiber laser with high power output potential and all fiber structure is determined. Secondly, the basic principle of polarization mode selection of polarization-maintaining grating is introduced, and an all-fiber linear polarization fiber laser oscillator based on this principle is realized. The output of 42.3 W linear polarization laser is realized, and the extinction ratio is better than 14 dB.. The effects of grating temperature and polarization crosstalk on the output characteristics of the linear polarization fiber laser are studied and analyzed experimentally. The characteristics of this type of linear polarization fiber laser are pointed out. An effective way to increase the output power and improve the output characteristics of this type of laser is presented. At the same time, the basic principle of polarization mode selection of bending loss is introduced. The bending loss of Panda polarization-maintaining fiber is simulated numerically, and an all-fiber linear polarization fiber laser oscillator based on this principle is realized. The output of 93.2 W linearly polarized laser is achieved, and the extinction ratio is better than 15.3 dB, which is the highest output power of the linear polarization fiber laser oscillator based on this principle. The relationship between the output characteristics of the laser and bending loss, grating parameters, grating temperature and polarization crosstalk is analyzed. The differences and advantages and disadvantages between this type of laser and linear polarization fiber laser oscillator based on polarization-maintaining grating polarization mode selection principle are compared and analyzed. This paper presents a way to improve and enhance the output characteristics of all-fiber linear polarization fiber laser without polarizing state selection device. It can be used for reference and guidance to obtain higher power, higher extinction ratio and better stability of linear polarization laser apparatus. Furthermore, the linear polarization fiber laser oscillator based on the principle of bending loss polarization mode selection is used as the seed laser, and the high power, high efficiency and high extinction ratio of the linear polarization fiber laser are successfully realized by using the first-order MOPA scheme. The maximum output power is 1491 W, the slope efficiency is 82.6%, the extinction ratio is better than 13.8dB, the M2 factor is about 1.2, which is the highest output power of linear polarization fiber laser reported. At the same time, a rate equation model considering amplified spontaneous emission and stimulated Raman scattering is used to analyze the potential of the scheme for further power enhancement.
【學位授予單位】：國防科學技術(shù)大學
【學位級別】：碩士
【學位授予年份】：2015
【分類號】：TN24

【參考文獻】

相關(guān)期刊論文 前4條

1 劉澤金;冷進勇;郭少鋒;王文亮;黃良金;曹澗秋;司磊;許曉軍;陳金寶;;全光纖結(jié)構(gòu)2kW準單模光纖激光器[J];中國激光;2013年09期

2 代守軍;何兵;周軍;趙純;陳曉龍;劉馳;;1.5kW近單模全光纖激光器[J];中國激光;2013年07期

3 閆平;肖起榕;付晨;王亞平;鞏馬理;;1.6kW全光纖摻鐿激光器[J];中國激光;2012年04期

4 段開椋;趙保銀;趙衛(wèi);王屹山;周良;;1000W全光纖激光器[J];中國激光;2009年12期

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