荸通扒2017年第62卷第32期:3719~3728 《中国科学》杂志社 香山杵李个认专栏」 SCIENCE CHINA PRESS 第570次学术讨论会·高功率高光束质量半导体激光技术发展战略 高功率、高光束质量半导体激光器硏究进展 张俊12,陈泳屹12,秦莉12,彭航宇12,宁永强1,王立军12 1.中国科学院长春光学精密机械与物理研究所,长春130033 2.发光学及应用国家重点实验室,长春130033 十同等贡献 联系人,E-mal: penghu@ ciompac cn 017-03-26收稿,2017-06-05修回,2017-06-05接受,2017-09-07网络版发表 国家自然科学基金(61574141,61404137,61535013,L1524007)、中国科学院学部学科发展战略研究项目(2015-XXC-2)和中国科学院前沿科 学重点研究项目( QYZDY-SSW-JSC006资助 摘要半导体激光器拥有效率高、体积小、重量轻、寿命长、波长丰富和可直接电驱动等诸多优点,同时由于 受到光束质量限制,难以直接进行应用.如何提升高功率半导体激光器的光束质量一直以来都是国内外研究热点 本文主要面向工业加工及国防等领域对高功率、高光束质量半导体激光器的应用需求,从半导体激光单元技术和 合束技术两方面的研究进展进行了论述.首先分析了激光单元结构与激光侧向、横向和纵向模式的关系,总结了 国际上控制模式特性的一些典型结构;然后介绍了当前国际上高功率、高光束质量半导体激光合東技术及光源发 展现状,并分析讨论了各种激光合束技术特点及发展趋势;最后展望了高功率、高光束质量半导体激光器的发展 前景 关键词半导体激光器,高功率,高光束质量,激光合束 与其他类型激光器相比,半导体激光器效率高的重大挑战.为此,美国和德国相继部署了 ADHEL (达70%)、体积小(体积<0.1cm3)、重量轻(100W激光 BRIDLE及 MOTHEB等专项,国内也在开展相关研究 芯片质量仅数克)、寿命长(数万小时)、波长丰富(可 见至红外任意波长输出)及可直接电驱动.早期对大 半导体激光单元技术的研究进展 功率半导体激光器的研究集中在如何提升功率,如 目前,实用化的高功率半导体激光单元器件主 增加发光区条宽提高单元功率,再二维集成提高整要基于边发射结构,根据芯片外延和激光振荡特性, 体功率,但与此同时导致光束质量下降,使其主要作光场模式分布在谐振腔的3个方向上,即垂直于PN结 为全固态激光器的泵浦源间接应用,难以直接应用.的横模、平行于PN结的侧模和沿着光轴方向的纵模 研究人员逐渐认识到半导体激光器的光束质量是与根据不同的使用条件,采用不同方式控制各方向模 功率同等重要的参数,提升高功率半导体激光器的式.下面从这3个方面介绍半导体激光单元技术的研 光束质量是半导体激光器走向直接应用必须攻克的究进展 难关,如何获得高功率、高光束质量半导体激光器成 为国际半导体激光科学的研究前沿,高功率、近衍射1.1侧向模式控制研究进展 极限单元器件及合束光源成为半导体激光技术领域中 高功率半导体激光单元器件的侧向模式是限制 引用棓式:张俊,陈泳屹,秦莉,等.高功率、高光束质量半导体激光器研究进展.科学通报,2017,62:3719-3728 Zhang J, Chen Y Y, Qin L et al. Advances in high power high beam quality diode lasers (in Chinese). Chin Sci Bull. 2017, 62: 3719-3728 doi 0.1360N972017-00352 ②2017《中国科学》杂志社 www.scichina.comcsb.scichina.com
2017 年 第 62 卷 第 32 期：3719 ~ 3728 引用格式: 张俊, 陈泳屹, 秦莉, 等. 高功率、高光束质量半导体激光器研究进展. 科学通报, 2017, 62: 3719–3728 Zhang J, Chen Y Y, Qin L, et al. Advances in high power high beam quality diode lasers (in Chinese). Chin Sci Bull, 2017, 62: 3719–3728, doi: 10.1360/N972017-00352 © 2017《中国科学》杂志社 www.scichina.com csb.scichina.com 《中国科学》杂志社 专栏 进 展 SCIENCE CHINA PRESS 第570次学术讨论会 • 高功率高光束质量半导体激光技术发展战略 高功率、高光束质量半导体激光器研究进展 张俊 1,2, 陈泳屹 1,2†, 秦莉 1,2†, 彭航宇 1,2*, 宁永强 1,2, 王立军 1,2 1. 中国科学院长春光学精密机械与物理研究所, 长春 130033; 2. 发光学及应用国家重点实验室, 长春 130033 † 同等贡献 * 联系人, E-mail: penghy@ciomp.ac.cn 2017-03-26 收稿, 2017-06-05 修回, 2017-06-05 接受, 2017-09-07 网络版发表 国家自然科学基金(61574141, 61404137, 61535013, L1524007)、中国科学院学部学科发展战略研究项目(2015-XX-C-2)和中国科学院前沿科 学重点研究项目(QYZDY-SSW-JSC006)资助 摘要 半导体激光器拥有效率高、体积小、重量轻、寿命长、波长丰富和可直接电驱动等诸多优点, 同时由于 受到光束质量限制, 难以直接进行应用. 如何提升高功率半导体激光器的光束质量一直以来都是国内外研究热点. 本文主要面向工业加工及国防等领域对高功率、高光束质量半导体激光器的应用需求, 从半导体激光单元技术和 合束技术两方面的研究进展进行了论述. 首先分析了激光单元结构与激光侧向、横向和纵向模式的关系, 总结了 国际上控制模式特性的一些典型结构; 然后介绍了当前国际上高功率、高光束质量半导体激光合束技术及光源发 展现状, 并分析讨论了各种激光合束技术特点及发展趋势; 最后展望了高功率、高光束质量半导体激光器的发展 前景. 关键词 半导体激光器, 高功率, 高光束质量, 激光合束 与其他类型激光器相比, 半导体激光器效率高 (达70%)、体积小(体积<0.1 cm3 )、重量轻(100 W激光 芯片质量仅数克)、寿命长(数万小时)、波长丰富(可 见至红外任意波长输出)及可直接电驱动. 早期对大 功率半导体激光器的研究集中在如何提升功率, 如 增加发光区条宽提高单元功率, 再二维集成提高整 体功率, 但与此同时导致光束质量下降, 使其主要作 为全固态激光器的泵浦源间接应用, 难以直接应用. 研究人员逐渐认识到半导体激光器的光束质量是与 功率同等重要的参数, 提升高功率半导体激光器的 光束质量是半导体激光器走向直接应用必须攻克的 难关, 如何获得高功率、高光束质量半导体激光器成 为国际半导体激光科学的研究前沿, 高功率、近衍射 极限单元器件及合束光源成为半导体激光技术领域中 的重大挑战. 为此, 美国和德国相继部署了ADHEL, BRIDLE及IMOTHEB等专项, 国内也在开展相关研究. 1 半导体激光单元技术的研究进展 目前, 实用化的高功率半导体激光单元器件主 要基于边发射结构, 根据芯片外延和激光振荡特性, 光场模式分布在谐振腔的3个方向上, 即垂直于PN结 的横模、平行于PN结的侧模和沿着光轴方向的纵模. 根据不同的使用条件, 采用不同方式控制各方向模 式. 下面从这3个方面介绍半导体激光单元技术的研 究进展. 1.1 侧向模式控制研究进展 高功率半导体激光单元器件的侧向模式是限制
荸通扳2017年11月第6卷第32期 光束质量的主要因子.高功率和高光束质量是相互 DBR-grating 矛盾的指标,为了获得高功率,侧向发光区尺寸通常 RW-section 越大越好(百微米量级),但这又导致侧向光场模式限 制变弱,光束质量变差(数十倍衍射极限).为了均衡 Tapered section 功率和光束质量,通常采用线亮度(B1a)评价,定义为 激光功率P与侧向光束质量Qua的比值,B1a越大,单元 器件功率、光束质量综合指标越好 通过刻蚀成窄脊结构,减小侧向尺寸至微米量 级,可提升侧向光束质量.瑞士Ocao研制脊宽6μm、图2(网络版彩色)带有DBR光栅的锥形激光器示意图 斯光束输出,B1a达64W/( mm mrad),最大光电转换 效率63%.美国麻省理工采用板条耦合结构,应用在一些特殊场合,未能大面积推广应用 如图1所示,脊宽4μm、波导宽度5μm、腔长10mm 中国科学院半导体研究所、北京工业大学、中国 的半导体激光器获得了连续输出3W、B比89科学院长春光学精密机械与物理研究所、长春理工大 W/( mm mrad的1060mm单模激光输出,最大光电转学均在MOPA结构的LD研究中取得了初步成果,其 换效率45%.窄脊激光器提升B1具有很好的效果,中长春理工大学的MOPA结构LD输出功率可以达到 但由于腔面尺寸小,高功率输出时腔面功率密度高,6W@线功率密度17mWum,所报道功率水平最高 容易造成腔面损伤,需要特殊的腔面钝化处理. 中国工程物理研究院应用电子学研究所通过多年研 为了降低腔面功率密度,同时提高激光功率,提究高亮度LD输出功率可以达到43W@9xm,光束 出了种子振荡功率放大器(MOPA)结构,它通过窄脊质量M2<4;在8xxnm波段国内只有中国科学院长春 单模激光源产生种子光,即振荡源(MO,经过半导光学精密机械与物理研究所做了MOPA结构LD的相 体放大器(PA将振荡源激光放大,当MO激光和关研究,实现输出功率14W@线功率密度11mwWμm, PA放大器集成到一个芯片上时就形成锥形激光器,M2-2.8 同时还可以在芯片上集成光栅结构调制光谱线宽 德国FBH研究所也采用侧向反引导结构,引入 德国FBH( Ferdinand- Braun- nstitute研究所先后报道高阶模损耗机制,压制高阶模起振,改善光束质量, 了多种波长的锥形激光器,如图2所示,808mm条宽90μm、腔长4mm的969mm激光单元,实现连续 波长M=1.3×39W,B1为16W/ mm mrad)3;9797w激光输出,Bu达到3.W/( mm mrad),同时压 nm波长M2u2=1.1×14W,B1为33W/( mm mrad16,缩侧向尺寸至20和30um2,采用腔长6mm结构,B1 1030nm波长M2d2=1.2×14.5W,B1a为36.8W/mm分别达到6.5和55W/( mm mrad). OSRAM在迷你bar mrad)1;,1060nm波长M2=1.2×10W,B1为24.7上集成5个条宽50um的激光单元,输出功率达到 W/ mm mrad)18.在高功率输出条件下实现了高光50w,光束质量优于11 mm mrad,B达到4.8W/m 束质量输出,但由于工艺复杂、制作难度大,目前仅mrad21 美国 nIgh公司提出喇叭形结构( flared oscillator Quantum well region p-type contact waveguide diodes)223,在谐振腔侧向制备锥形结构 通过侧向最小位置限制横向模式,出光腔面保持大 尺寸,降低腔面功率密度,输出功率13W,光束质量 3 mm mrad, Blat/]4.3 W/(mm mrad) 5 um n-type contact 1.2横向模式控制硏兖进展 1(网络版彩色)板条耦合半导体激光单元结构(a)和近场模式分 2002年,柏林工业大学的 Ledentsov等人P21在 Figure( Color online) Structure of the slab coupled diode laser emit.横向利用周期性生长的半导体材料层构成带隙光子 ter(a)and near-fieldmode pattern(b) 晶体结构①LPBC,限制横向模式,在保持横向光束 3720
2017 年 11 月 第 62 卷 第 32 期 3720 光束质量的主要因子. 高功率和高光束质量是相互 矛盾的指标, 为了获得高功率, 侧向发光区尺寸通常 越大越好(百微米量级), 但这又导致侧向光场模式限 制变弱, 光束质量变差(数十倍衍射极限). 为了均衡 功率和光束质量, 通常采用线亮度(Blat)评价, 定义为 激光功率P与侧向光束质量Qlat的比值, Blat越大, 单元 器件功率、光束质量综合指标越好. 通过刻蚀成窄脊结构, 减小侧向尺寸至微米量 级, 可提升侧向光束质量. 瑞士Oclaro研制脊宽6 μm、 腔长4.8 mm的980 nm激光单元, 实现连续2 W基模高 斯光束输出, Blat达6.4 W/(mm mrad), 最大光电转换 效率63%[1]. 美国麻省理工采用板条耦合结构[2~5], 如图1所示, 脊宽4 μm、波导宽度5 μm、腔长10 mm 的半导体激光器获得了连续输出3 W、Blat比8.9 W/(mm mrad)的1060 nm单模激光输出, 最大光电转 换效率45%[6]. 窄脊激光器提升Blat具有很好的效果, 但由于腔面尺寸小, 高功率输出时腔面功率密度高, 容易造成腔面损伤, 需要特殊的腔面钝化处理. 为了降低腔面功率密度, 同时提高激光功率, 提 出了种子振荡功率放大器(MOPA)结构, 它通过窄脊 单模激光源产生种子光, 即振荡源(MO), 经过半导 体放大器(PA)将振荡源激光放大[7~10], 当MO激光和 PA放大器集成到一个芯片上时就形成锥形激光器, 同时还可以在芯片上集成光栅结构调制光谱线宽. 德国FBH(Ferdinand-Braun-Institut)研究所先后报道 了多种波长的锥形激光器[11~14], 如图2所示, 808 nm 波长M2 =1.3×3.9 W, Blat为11.66 W/(mm mrad)[15]; 979 nm波长M2 (1/e2)=1.1×11.4 W, Blat为33 W/(mm mrad)[16]; 1030 nm波长M2 (1/e2)=1.2×14.5 W, Blat为36.8 W/(mm mrad)[17]; 1060 nm波长M2 =1.2×10 W, Blat为24.7 W/(mm mrad)[18]. 在高功率输出条件下实现了高光 束质量输出, 但由于工艺复杂、制作难度大, 目前仅 图 1 (网络版彩色)板条耦合半导体激光单元结构(a)和近场模式分 布(b) Figure 1 (Color online) Structure of the slab coupled diode laser emitter (a) and near-fieldmode pattern (b) 图 2 (网络版彩色)带有DBR光栅的锥形激光器示意图 Figure 2 (Color online) The typical tapered laser with DBR gratings 应用在一些特殊场合, 未能大面积推广应用. 中国科学院半导体研究所、北京工业大学、中国 科学院长春光学精密机械与物理研究所、长春理工大 学均在MOPA结构的LD研究中取得了初步成果, 其 中长春理工大学的MOPA结构LD输出功率可以达到 6 W@线功率密度17 mW/μm, 所报道功率水平最高; 中国工程物理研究院应用电子学研究所通过多年研 究高亮度LD输出功率可以达到4.3 W@9xx nm, 光束 质量M2 <4; 在8xx nm波段国内只有中国科学院长春 光学精密机械与物理研究所做了MOPA结构LD的相 关研究, 实现输出功率1.4 W@线功率密度11 mW/μm, M2 ~2.8. 德国FBH研究所也采用侧向反引导结构, 引入 高阶模损耗机制, 压制高阶模起振, 改善光束质量, 条宽90 μm、腔长4 mm的969 nm激光单元, 实现连续 7 W激光输出, Blat达到3.5 W/(mm mrad)[19], 同时压 缩侧向尺寸至20和30 μm[20], 采用腔长6 mm结构, Blat 分别达到6.5和5.5 W/(mm mrad). OSRAM在迷你bar 上集成5个条宽50 μm的激光单元, 输出功率达到 50 W, 光束质量优于11 mm mrad, Blat达到4.8 W/(mm mrad)[21]. 美国nLigh公司提出喇叭形结构(flared oscillator waveguide diodes)[22,23], 在谐振腔侧向制备锥形结构, 通过侧向最小位置限制横向模式, 出光腔面保持大 尺寸, 降低腔面功率密度, 输出功率13 W, 光束质量 3 mm mrad, Blat为4.3 W/(mm mrad). 1.2 横向模式控制研究进展 2002年, 柏林工业大学的Ledentsov等人[24,25]在 横向利用周期性生长的半导体材料层构成带隙光子 晶体结构(LPBC), 限制横向模式, 在保持横向光束
质量近衍射极限条件下,增加横向波导尺寸,同时降中国科学院长春光学精密机械与物理研究所研制出 低横向发散角.该结构的好处在于,横向波导尺寸的38阶光栅耦合DBR半导体激光器,获得213mW、线 增加有效地降低腔面功率密度,使得激光单元腔面宽40pm单纵模出光,边模抑制比40dB3 可承受更高功率,提升高功率工作下的可靠性,其次 (ⅱ)分布反馈(DFB)半导体激光器.国外从 直接输出低发散角的激光束,采用球面透镜准直即2004年开始高功率DFB半导体激光器的研究,如德 可.但是较厚的有源区也限制了激光器效率.表1总国PBH研究所研制出976nm的一阶和二阶光栅器件, 结了LPBC半导体激光单元的发展现状4-36-3.柏林稳定基横模激射,输出功率分别为400mW和2.4 工业大学报道了系列研究结果,将横向发散角压缩W+,转换效率356%;美国 Alfalight公司报道了 至度量级.中国科学院长春光学精密机械与物理研975nm二阶光栅器件,条宽100μm、腔长2mm的DFB 究所采用双边布拉格反射波导结合低折射率光缺陷激光器,连续输出功率3W、电光转换效率50%、线 层结构,在808m波长获得了近圆形光束输出,90宽03mm142;韩国 Gwangju科学院和加拿大国立研究 um条宽、15mm腔长单管连续输出功率35W,4mm院研制的1.55m三阶和二阶光栅DFB,单纵模功率 腔长连续功率4.6W,橫向发散角降至491 为15mW;美国 Eagleyard公司的976nm的DFB 激光器,单纵模输出功率150mW( Eagleyard.EYP 1.3纵向模式控制研究进展 DFB0976-00150-1500TOC03-0000EB/OL].www.eag 对于高功率半导体激光器,常采用光栅控制纵 leyard. com)中国科学院长春光学精密机械与物理 向模式,这里主要在芯片结构上制备光栅:一是处于研究所研制出9688m增益耦合DFB激光器,实现了 腔面的分布布拉格反射DBR结构;一是分布在谐振1446mW、线宽40pm单模出光,边模抑制比29 腔内的分布反馈结构(DFB) dB,;设计并研制出940nm二阶光栅DFB半导体激 (i)分布布拉格反射DBR)激光器.DBR激光器,连续输出101mW、光谱线宽9 器以布拉格光栅作为激光器的一个谐振腔面.2010角为27°和73°、边模抑制比20dB、远场发散 年,德国HBH研究所采用表面DBR结构获得了高功2高光束质量半导体激光合束光源的研究 率激光输出,90um条宽单管输出功率14W,最大转 换效率为50%.同年,他们采用六阶表面光栅结 进展 构,在激射波长974nm,单模输出功率超过1W,3dB 大功率半导体激光器根据单芯片集成的单元数 光谱线宽仅为14MHz.2011年,研制出1064 nmDBR量可分为激光单管( emitter、激光线阵(ba)和激光叠 激光器,连续输出功率180mW、线宽为180kHz.阵( stack).激光线阵为多个单管在水平方向的集成 表1带隙光子晶体波导激光器发展现状 Table 1 Research status of photonic crystal waveguide diode laser 波段(nm) 年份 研制单位 发散角及相关性能指标 横向 横向55°-612 柏林工业大学 横向97°-107°,连续1.8W,脉冲10W12n 980 横向4°-5°,侧向3.5°,连续1.3W1281 横向6°,侧向5°,连续22W,光参量积047 mm mrad 中国科学院半导体研究所横向10.5°,200μm条宽连续输出功率575W1 横向15°,侧向9°,峰值功率3W 1060 2015 柏林工业大学 横向15°,侧向11°,6μm条宽、2.64mm腔长,连续1.8w M=1.55.9μm条宽功率1.9W 2015中国科学院长春光学精密横向491.4m长连续46w 机械与物理研究所 3721
3721 进 展 质量近衍射极限条件下, 增加横向波导尺寸, 同时降 低横向发散角. 该结构的好处在于, 横向波导尺寸的 增加有效地降低腔面功率密度, 使得激光单元腔面 可承受更高功率, 提升高功率工作下的可靠性, 其次 直接输出低发散角的激光束, 采用球面透镜准直即 可. 但是较厚的有源区也限制了激光器效率. 表1总 结了LPBC半导体激光单元的发展现状[24,26~34]. 柏林 工业大学报道了系列研究结果, 将横向发散角压缩 至度量级. 中国科学院长春光学精密机械与物理研 究所采用双边布拉格反射波导结合低折射率光缺陷 层结构, 在808 nm波长获得了近圆形光束输出, 90 μm条宽、1.5 mm腔长单管连续输出功率3.5 W, 4 mm 腔长连续功率4.6 W, 横向发散角降至4.91°. 1.3 纵向模式控制研究进展 对于高功率半导体激光器, 常采用光栅控制纵 向模式, 这里主要在芯片结构上制备光栅: 一是处于 腔面的分布布拉格反射(DBR)结构; 一是分布在谐振 腔内的分布反馈结构(DFB). (ⅰ) 分布布拉格反射(DBR)激光器. DBR激光 器以布拉格光栅作为激光器的一个谐振腔面. 2010 年, 德国FBH研究所采用表面DBR结构获得了高功 率激光输出, 90 μm条宽单管输出功率14 W, 最大转 换效率为50%[35]. 同年, 他们采用六阶表面光栅结 构, 在激射波长974 nm, 单模输出功率超过1 W, 3 dB 光谱线宽仅为1.4 MHz[36]. 2011年, 研制出1064 nmDBR 激光器, 连续输出功率180 mW、线宽为180 kHz[37]. 中国科学院长春光学精密机械与物理研究所研制出 38阶光栅耦合DBR半导体激光器, 获得213 mW、线 宽40 pm单纵模出光, 边模抑制比40 dB[38]. (ⅱ) 分布反馈(DFB)半导体激光器. 国外从 2004年开始高功率DFB半导体激光器的研究, 如德 国FBH研究所研制出976 nm的一阶和二阶光栅器件, 稳定基横模激射, 输出功率分别为400 mW和2.4 W[39~41], 转换效率35.6%; 美国Alfalight公司报道了 975 nm二阶光栅器件, 条宽100 μm、腔长2 mm的DFB 激光器, 连续输出功率3 W、电光转换效率50%、线 宽0.3 nm[42]; 韩国Gwangju科学院和加拿大国立研究 院研制的1.55 μm三阶和二阶光栅DFB, 单纵模功率 为15 mW[43,44]; 美国Eagleyard公司的976 nm的DFB 激光器, 单纵模输出功率150 mW(Eagleyard. EYPDFB-0976-00150-1500-TOC03-0000[EB/OL]. www.eagleyard.com). 中国科学院长春光学精密机械与物理 研究所研制出968.8 nm增益耦合DFB激光器, 实现了 144.6 mW、线宽40 pm单模出光, 边模抑制比29 dB[45]; 设计并研制出940 nm二阶光栅DFB半导体激 光器, 连续输出101 mW、光谱线宽90 pm、远场发散 角为2.7°和7.3°、边模抑制比20 dB[46]. 2 高光束质量半导体激光合束光源的研究 进展 大功率半导体激光器根据单芯片集成的单元数 量可分为激光单管(emitter)、激光线阵(bar)和激光叠 阵(stack). 激光线阵为多个单管在水平方向的集成, 表 1 带隙光子晶体波导激光器发展现状 Table 1 Research status of photonic crystal waveguide diode laser 波段(nm) 年份 研制单位 发散角及相关性能指标 980 2002 柏林工业大学 横向6°[24] 2003 横向5.5°~6°[26] 2005 横向9.7°~10.7°, 连续1.8 W, 脉冲10 W[27] 2008 横向4°~5°, 侧向3.5°, 连续1.3 W[28] 2010 横向6°, 侧向5°, 连续2.2 W, 光参量积0.47 mm mrad[29] 2014 中国科学院半导体研究所 横向10.5°, 200 μm条宽连续输出功率5.75 W[30] 1060 2014 柏林工业大学 横向15°, 侧向9°, 峰值功率3 W[31] 2015 横向15°, 侧向11°, 6 μm条宽、2.64 mm腔长, 连续1.8 W[32] 2016 M2 =1.55, 9 μm条宽功率1.9 W[33] 808 2015 中国科学院长春光学精密 机械与物理研究所 横向4.91°, 4 mm腔长连续4.6 W[34]
荸通扳2017年11月第6卷第32期 可连续输出几十瓦至数百瓦功率,主流结构为条宽偏振合束和波长合束来提升整体功率、改善整体光束 为10mm的标准bar( cm bar)或者条宽小于10mm的迷质量的过程 你bar( mini bar,通常采用传导热沉或者微通道去离根据激光单管、线阵和叠阵3种不同的封装形式, 子水冷却热沉封装.激光叠阵为多个微通道去离子借助常规合束技术,目前已发展出激光单管合束光 水冷却热沉封装线阵在垂直方向的集成,可以连续源、线阵合束光源和叠阵合束光源,实现了几十瓦至 输出百瓦至数千瓦的功率.提高半导体激光器功率数万瓦级的直接输出或光纤耦合输出,应用在光纤 可通过空间集成多个单管、线阵或叠阵,而如何获得激光泵浦、激光加工等 高光束质量,需要进行激光合束 单管合束光源是基于慢轴光束质量相对好的激 当前实用化的高功率半导体激光合束光源主要光单管,快慢轴准直后,直接通过空间合束、偏振合 基于非相干合束技术,发展经历了传统合束技术束及波长合束实现耦合,可实现单波长几十瓦至六 (TBC)到密集波长合束DWDM和光谱合束(WBC)并百瓦功率从100~200μm芯径光纤输出,光束质量6 行发展两个阶段,如图3所示.1998-207年,主要采20 mm mrad,具有亮度高、成本低及可靠性好等优 用常规合束技术,由于激光单元性能的功率指标提点,应用在光纤激光泵浦、激光医疗、激光照明等领 升和常规合束技术的逐渐成熟,相同功率激光的光域.美国 nLight和日本 Fujikura近期相继报道采用高 束质量提高近10倍.2007~2017年,随着芯片结构优功率、高光束质量的激光单管,将105μm光纤耦合单 化及元器件性能提升,常规合束光源(TBC)的光束质波长模块功率从100W提升至250W4-4,用于光纤 量提高近5倍,部分达到灯泵固体激光器( LPSSL)水激光器泵浦,提升光纤激光器性能.意大利OPI公司 平,密集波长合束(WBC)和光谱合束(SBC为半导体通过波长合束进一步提高功率,105μm/0.15光纤输 激光技术领域注入新的活力,使得直接半导体激光出300W功率.北京凯普林通过空间叠加激光单管 源光束质量提高近15倍,超过 LPSSL,达到CO2激光和偏振合束,200um/022光纤输出600w15n 器水平.这也使得高功率半导体激光器在“间接应用 线阵合束光源多采用传导热沉封装、光束质量相 泵浦全固态激光器→直接应用熔覆、塑料焊接等功率对较好的迷你bar(5-10个激光单元)或者低填充因子 密度低的场合→直接应用在金属焊接、切割等高端加的厘米bar(填充因子<20%).主要原因在于常规的厘 工市场”的道路上快速稳健地前进. 米bar(填充因子≥20%),慢轴方向光束质量差,需要 21常规合束(TBC)技术及进展 光束整形,光学结构复杂,加上散热限制单个激光线 阵的输出功率一般在40-80W,不能发挥厘米bar的 常规合束基于输出性能最佳的常规激光单元,功率优势.线阵合束光源功率一般在几百瓦至数千 合束过程中,不影响激光单元腔内谐振,仅通过外部瓦,200-600μm芯径光纤输出,光束质量20-60mm 光学元件对输出单元激光进行光束整形、空间合束、mrad,主要应用在激光焊接等工业加工.代表性的 厂商包括德国Dlas, Trumpf,Limo等23.德国Dias ▲DwoM 1000 公司采用 OSRAM研制的新一代高性能迷你bar (Ba-4.8W/( mm mrad),将其225m光纤输出标准 产品功率从270W提升至360W的,并通过偏振合束 和5个波长合束,400m/0.12光纤输出4600W58 叠阵合束光源借助微通道去离子水的高效散热, 采用高填充因子厘米bar,单层激光叠阵功率可达数 百瓦,经过数十层叠阵合束,能够实现数千瓦到万瓦 cw31000,通过波长合束可将功率提升到更高水平德国 Laserline基于高亮度的激光叠阵,研发出系列高功率 图3(网络版彩色高功率半导体激光合束光源功率光束质量研究光纤耦合产品,连续输出功率从3kW(400m0.1)到 进展 Ire 3 online) Power vs beam quality research progress on 20kW(2000um/0.2)9,并报道了连续输出25-40 aser combining sources kW(2000pm/0.2)的多波长合束光源061.目前叠阵 3722
2017 年 11 月 第 62 卷 第 32 期 3722 可连续输出几十瓦至数百瓦功率, 主流结构为条宽 为10 mm的标准bar(cm bar)或者条宽小于10 mm的迷 你bar(mini bar), 通常采用传导热沉或者微通道去离 子水冷却热沉封装. 激光叠阵为多个微通道去离子 水冷却热沉封装线阵在垂直方向的集成, 可以连续 输出百瓦至数千瓦的功率. 提高半导体激光器功率 可通过空间集成多个单管、线阵或叠阵, 而如何获得 高光束质量, 需要进行激光合束. 当前实用化的高功率半导体激光合束光源主要 基于非相干合束技术, 发展经历了传统合束技术 (TBC)到密集波长合束(DWDM)和光谱合束(WBC)并 行发展两个阶段, 如图3所示. 1998~2007年, 主要采 用常规合束技术, 由于激光单元性能的功率指标提 升和常规合束技术的逐渐成熟, 相同功率激光的光 束质量提高近10倍. 2007~2017年, 随着芯片结构优 化及元器件性能提升, 常规合束光源(TBC)的光束质 量提高近5倍, 部分达到灯泵固体激光器(LPSSL)水 平, 密集波长合束(WBC)和光谱合束(SBC)为半导体 激光技术领域注入新的活力, 使得直接半导体激光 源光束质量提高近15倍, 超过LPSSL, 达到CO2激光 器水平. 这也使得高功率半导体激光器在“间接应用 泵浦全固态激光器→直接应用熔覆、塑料焊接等功率 密度低的场合→直接应用在金属焊接、切割等高端加 工市场”的道路上快速稳健地前进. 2.1 常规合束(TBC)技术及进展 常规合束基于输出性能最佳的常规激光单元, 合束过程中, 不影响激光单元腔内谐振, 仅通过外部 光学元件对输出单元激光进行光束整形、空间合束、 图 3 (网络版彩色)高功率半导体激光合束光源功率-光束质量研究 进展 Figure 3 (Color online) Power vs beam quality research progress on high power diode laser combining sources 偏振合束和波长合束来提升整体功率、改善整体光束 质量的过程. 根据激光单管、线阵和叠阵3种不同的封装形式, 借助常规合束技术, 目前已发展出激光单管合束光 源、线阵合束光源和叠阵合束光源, 实现了几十瓦至 数万瓦级的直接输出或光纤耦合输出, 应用在光纤 激光泵浦、激光加工等. 单管合束光源是基于慢轴光束质量相对好的激 光单管, 快慢轴准直后, 直接通过空间合束、偏振合 束及波长合束实现耦合, 可实现单波长几十瓦至六 百瓦功率从100~200 μm芯径光纤输出, 光束质量6~ 20 mm mrad, 具有亮度高、成本低及可靠性好等优 点, 应用在光纤激光泵浦、激光医疗、激光照明等领 域. 美国nLight和日本Fujikura近期相继报道采用高 功率、高光束质量的激光单管, 将105 μm光纤耦合单 波长模块功率从100 W提升至250 W[47~49], 用于光纤 激光器泵浦, 提升光纤激光器性能. 意大利OPI公司 通过波长合束进一步提高功率, 105 μm/0.15光纤输 出300 W功率[50]. 北京凯普林通过空间叠加激光单管 和偏振合束, 200 μm/0.22光纤输出600 W[51]. 线阵合束光源多采用传导热沉封装、光束质量相 对较好的迷你bar(5~10个激光单元)或者低填充因子 的厘米bar(填充因子<20%). 主要原因在于常规的厘 米bar(填充因子≥20%), 慢轴方向光束质量差, 需要 光束整形, 光学结构复杂, 加上散热限制单个激光线 阵的输出功率一般在40~80 W, 不能发挥厘米bar的 功率优势. 线阵合束光源功率一般在几百瓦至数千 瓦, 200~600 μm芯径光纤输出, 光束质量20~60 mm mrad, 主要应用在激光焊接等工业加工. 代表性的 厂商包括德国Dilas, Trumpf, Limo等[52~56]. 德国Dilas 公司采用 OSRAM 研制的新一代高性能迷你 bar (Blat~4.8 W/(mm mrad)), 将其225 μm光纤输出标准 产品功率从270 W提升至360 W[57], 并通过偏振合束 和5个波长合束, 400 μm/0.12光纤输出4600 W[58]. 叠阵合束光源借助微通道去离子水的高效散热, 采用高填充因子厘米bar, 单层激光叠阵功率可达数 百瓦, 经过数十层叠阵合束, 能够实现数千瓦到万瓦 功率, 通过波长合束可将功率提升到更高水平. 德国 Laserline基于高亮度的激光叠阵, 研发出系列高功率 光纤耦合产品, 连续输出功率从3 kW(400 μm/0.1)到 20 kW(2000 μm/0.2)[59], 并报道了连续输出25~40 kW (2000 μm/0.2)的多波长合束光源[60,61]. 目前叠阵
合束光源多用于激光熔覆,表面硬化等对激光功率410Wo.德国LT通过ⅤBG将6个商用激光模块波 要求高、光束质量要求低的工业加工方面 长锁定至9359,940.1,944.0.972.5,976.5和979.7nm, 22密集波长合東(DwDM)技术及进展 然后采用二向分色镜进行密集波长合束和粗波长合 束及聚焦耦合进光纤,100μmO.17光纤输出超过800 相对于传统波长合束相邻波长间隔不低于25mmW6,德国 Directphotonics也实现了波长间隔为4nm 而言,密集波长合束可将波长间隔缩小至纳米量级,的5束激光合束6,目前该公司已推出了功率500 在不改变光束质量条件下,数倍增加激光单元数量,2000W、光束质量5 mm mrad、芯径100m的光纤耦 从而提高合束光源功率 合半导体激光源产品,应用在金属切割 密集波长合束实现的关键在于:(1)中心波长稳 德国RWTH以VBG作为合束元件,通过精密温 定的窄线宽激光单元,可以通过直接在芯片刻蚀光控4片相同ⅤBG,使其衍射波长和角度偏移,分别调 栅或者通过外腔体布拉格光栅(VBG反馈调制光谱;节至974.5,9760,977.5和979.0nm,实现5束中心波 (2)波长间隔小的合束元件,如高波长陡度的二向分长间隔仅为15nm激光合束 色元件、合束ⅤBG等 德国ⅡT研究所在迷你ba芯片上刻蚀不同周期2.3光谱合束(SBC技术及进展 光栅,5个激光单元输出如图4所示的激光波长62,中 光谱合束技术利用单片色散元件,可同时实现 波长间隔25nm,采用4个二向分色镜将5个单元激多束波长间隔低至01nm的激光合束,进一步提高合 光合束,并聚焦进35um光纤.该方法实现的窄线束单元数量 宽单元结构稳定,但是芯片光栅工艺要求非常高,难 目前发展较快,并已形成产品的光谱合束原理 度非常大,在芯片制备时一旦某个单元光谱相对于如图5所示,整个光源由前腔面镀增透膜的半导体激 位置出现偏差,严重影响合束效率. 光芯片、变换透镜、光栅和外腔镜组成,激光芯片输 VBG外腔反馈是当前实现窄线宽激光输出的主出多个单元光束经变换透镜作用,成像到光栅同一 要方式,在常规激光芯片前腔面镀增透膜,利用点,然后经光栅衍射,由外腔镜将衍射光部分反射回 VBG衍射光作为种子光反馈回芯片腔内起振,可实光栅,并沿原路返回,回到原激光单元的光起振,每 现谱宽窄至0.1nm、温度漂移0.olnm℃的激光输岀.个单元激光的起振波长严格满足光栅方程,由于光 德国 Dilas采用波长陡度为1nm的二向分色镜,对经栅入射角不同而衍射角相同,使得各激光单元起振 过ⅤBG线宽窄化处理的972,976和980nm3束线偏振在各自不同的波长,经过外腔镜输出的激光在近场 光波长合束并耦合进100μm/0.2光纤,出纤功率和远场均重合,因此实现功率为所有单元之和、光束 质量与单个激光单元一致的激光输出.美国麻省理 Output coupler 图4(网络版彩色)迷你bar输出波长间隔2nm的光谱分布 Figure4( Color online) Spectral distribution of five single emitters图5(网络版彩色)光谱合束原理 with the wavelength interval of 2 nm Figure 5( Color online) Principe of WBC
3723 进 展 合束光源多用于激光熔覆, 表面硬化等对激光功率 要求高、光束质量要求低的工业加工方面. 2.2 密集波长合束(DWDM)技术及进展 相对于传统波长合束相邻波长间隔不低于25 nm 而言, 密集波长合束可将波长间隔缩小至纳米量级, 在不改变光束质量条件下, 数倍增加激光单元数量, 从而提高合束光源功率. 密集波长合束实现的关键在于: (1) 中心波长稳 定的窄线宽激光单元, 可以通过直接在芯片刻蚀光 栅或者通过外腔体布拉格光栅(VBG)反馈调制光谱; (2) 波长间隔小的合束元件, 如高波长陡度的二向分 色元件、合束VBG等. 德国ILT研究所在迷你bar芯片上刻蚀不同周期 光栅, 5个激光单元输出如图4所示的激光波长[62], 中 心波长间隔2.5 nm, 采用4个二向分色镜将5个单元激 光合束, 并聚焦进35 μm光纤[63]. 该方法实现的窄线 宽单元结构稳定, 但是芯片光栅工艺要求非常高, 难 度非常大, 在芯片制备时一旦某个单元光谱相对于 位置出现偏差, 严重影响合束效率. VBG外腔反馈是当前实现窄线宽激光输出的主 要方式, 在常规激光芯片前腔面镀增透膜, 利用 VBG衍射光作为种子光反馈回芯片腔内起振, 可实 现谱宽窄至0.1 nm、温度漂移0.01 nm/℃的激光输出. 德国Dilas采用波长陡度为1 nm的二向分色镜, 对经 过VBG线宽窄化处理的972, 976和980 nm 3束线偏振 光波长合束并耦合进100 μm/0.2光纤, 出纤功率 图 4 (网络版彩色)迷你bar输出波长间隔 2 nm的光谱分布 Figure 4 (Color online) Spectral distribution of five single emitters with the wavelength interval of 2 nm 410 W[64]. 德国ILT通过VBG将6个商用激光模块波 长锁定至935.9, 940.1, 944.0, 972.5, 976.5和979.7 nm, 然后采用二向分色镜进行密集波长合束和粗波长合 束及聚焦耦合进光纤, 100 μm/0.17光纤输出超过800 W[65]; 德国Directphotonics也实现了波长间隔为4 nm 的5束激光合束[66,67], 目前该公司已推出了功率500~ 2000 W、光束质量5 mm mrad、芯径100 μm的光纤耦 合半导体激光源产品[68], 应用在金属切割. 德国RWTH以VBG作为合束元件, 通过精密温 控4片相同VBG, 使其衍射波长和角度偏移, 分别调 节至974.5, 976.0, 977.5和979.0 nm, 实现5束中心波 长间隔仅为1.5 nm激光合束[69]. 2.3 光谱合束(SBC)技术及进展 光谱合束技术利用单片色散元件, 可同时实现 多束波长间隔低至0.1 nm的激光合束, 进一步提高合 束单元数量. 目前发展较快, 并已形成产品的光谱合束原理 如图5所示, 整个光源由前腔面镀增透膜的半导体激 光芯片、变换透镜、光栅和外腔镜组成, 激光芯片输 出多个单元光束经变换透镜作用, 成像到光栅同一 点, 然后经光栅衍射, 由外腔镜将衍射光部分反射回 光栅, 并沿原路返回, 回到原激光单元的光起振, 每 个单元激光的起振波长严格满足光栅方程, 由于光 栅入射角不同而衍射角相同, 使得各激光单元起振 在各自不同的波长, 经过外腔镜输出的激光在近场 和远场均重合, 因此实现功率为所有单元之和、光束 质量与单个激光单元一致的激光输出. 美国麻省理 图 5 (网络版彩色)光谱合束原理 Figure 5 (Color online) Principe of WBC
荸通扳2017年11月第6卷第32期 工大学(MI)对该技术的发展做了很多工作2,现国FBH于2015年报道利用锁相技术实现两个迷你bar 产业化、成立 Teradiode/公司、推出了功率500W/50相干合束,如图7所示,输出功率11.5W,光束质量接 um、2-8kw/100um光纤输出产品、应用在厚板金近衍射极限,其中,每个bar包含5个锥形激光单元 属切割、远程激光焊接等,是同等功率下激光加工光 源的有力竞争者,并报道了360w、2倍衍射极限、3展望 亮度达10GW(cm2sr)的半导体激光源,直接将高功 半导体激光器正向着高功率、高光束质量(高亮 率半导体激光的亮度提高2个数量级,为高功率、高度)的方向快速发展,通过激光单元结构设计及模式 亮度半导体激光器发展指明新方向 限制,获得高光束质量激光输出,通过激光合束技 德国 Trumpf公司提出了一种基于带宽达pm量级术,实现千瓦、万瓦乃至更高功率.已实现的360 的窄带滤光片用于外腔反馈波长锁定结构,如图6W06 mm mrad,4680W/4 mm mrad,8000W/6mm 所示.通过镀膜,使窄带滤光片具有角度-波长筛选mrad指标,达到了同功率下CO2激光器和商用全固态 特性,只有同时满足入射角和波长条件的光才能透激光器的输出水平,极大地推动了高功率半导体激 过滤光片,这使得不同位置激光单元起振在不同波光器从泵浦应用发展到直接应用,结合其小体积、轻 长,实现波长调制.据文献报道,采用带宽50pm重量、高转换效率及宽光谱输出等特性,将在材料加 (FWHM的滤光片,将10个厘米bar波长锁定,整体工、成像探测、医疗、显示等领域获得广泛应用.在 输出谱宽为37nm,每个厘米bar谱宽34mm,每个激国防领域,半导体激光器将作为新一代小型化、轻量 光单元80 pm(FWHM,然后匹配合适的面光栅实现化的激光载荷光源,装备到车载、机载等机动性强的 合束,并耦合进100um芯径光纤中,输出功率近作战平台 500W16,利用该技术,已经从200m光纤输出超过 目前,我国在高端半导体激光芯片及合束光源 5 kwIn 方面与国外仍有一定差距.需要进一步提高半导体 上述的常规合束、密集波长合束和光谱合束技术激光芯片的功率和光束质量;攻克万瓦级激光合束 均为非相干合束,它是目前实现高功率半导体激光和光纤组束技术;解决光栅制造关键技术;亟待联 输出的主要方式 合国内优势单位进行攻关和突破,实现高端半导体 激光器产品的自主研发和生产 24相千合東 相干合束通过控制激光单元的波长、偏振及相位 等,使各单元的光束相干输出,在远场获得高功率、 高亮度激光.理论上可耦合无限个激光单元,但由于 该技术对激光单元的光谱、偏振及相位等都有严格要 Optical axis 求,需对每个单元进行控制,并随着合束激光单元的 Diode laser Fourier fas HR mirror 增多,控制的难度也急剧上升,目前未实用化 =565mm) 美国MIT于2011年报道通过种子注入控制激光 单元光谱,相位反馈驱动电流控制相位,实现了218图6(网络版彩色基于窄带滤光片的外腔反馈波长锁定结构 Figure 6(Color online) Structure of feedback cavity with wave- 个激光单元相干合束,获得385W功率输出8.德 length-locked by the narrowband filter Master DFB laser 1 Optical isolators l夏 图7(网络版彩色)2个迷你bar(5个锥形激光单元)相干合束实验示意图 Figure 7( Color online)CBC Experimental setup for two mini bar architecture with five MOPA emitters each 3724
2017 年 11 月 第 62 卷 第 32 期 3724 工大学(MIT)对该技术的发展做了很多工作[70~72], 现 产业化、成立Teradiode公司、推出了功率500 W/50 μm、2~8 kW/100 μm光纤输出产品[73]、应用在厚板金 属切割、远程激光焊接等, 是同等功率下激光加工光 源的有力竞争者, 并报道了360 W、2倍衍射极限[74]、 亮度达10 GW/(cm2 sr)的半导体激光源, 直接将高功 率半导体激光的亮度提高2个数量级, 为高功率、高 亮度半导体激光器发展指明新方向. 德国Trumpf公司提出了一种基于带宽达pm量级 的窄带滤光片用于外腔反馈波长锁定结构[75], 如图6 所示. 通过镀膜, 使窄带滤光片具有角度-波长筛选 特性, 只有同时满足入射角和波长条件的光才能透 过滤光片, 这使得不同位置激光单元起振在不同波 长, 实现波长调制. 据文献报道, 采用带宽50 pm (FWHM)的滤光片, 将10个厘米bar波长锁定, 整体 输出谱宽为37 nm, 每个厘米bar谱宽3.4 nm, 每个激 光单元80 pm(FWHM), 然后匹配合适的面光栅实现 合束, 并耦合进100 μm芯径光纤中, 输出功率近 500 W[76], 利用该技术, 已经从200 μm光纤输出超过 5 kW[77]. 上述的常规合束、密集波长合束和光谱合束技术 均为非相干合束, 它是目前实现高功率半导体激光 输出的主要方式. 2.4 相干合束 相干合束通过控制激光单元的波长、偏振及相位 等, 使各单元的光束相干输出, 在远场获得高功率、 高亮度激光. 理论上可耦合无限个激光单元, 但由于 该技术对激光单元的光谱、偏振及相位等都有严格要 求, 需对每个单元进行控制, 并随着合束激光单元的 增多, 控制的难度也急剧上升, 目前未实用化. 美国MIT于2011年报道通过种子注入控制激光 单元光谱, 相位反馈驱动电流控制相位, 实现了218 个激光单元相干合束, 获得38.5 W功率输出[78]. 德 国FBH于2015年报道利用锁相技术实现两个迷你bar 相干合束, 如图7所示, 输出功率11.5 W, 光束质量接 近衍射极限[79], 其中, 每个bar包含5个锥形激光单元. 3 展望 半导体激光器正向着高功率、高光束质量(高亮 度)的方向快速发展, 通过激光单元结构设计及模式 限制, 获得高光束质量激光输出, 通过激光合束技 术, 实现千瓦、万瓦乃至更高功率. 已实现的360 W/0.6 mm mrad, 4680 W/4 mm mrad, 8000 W/6 mm mrad指标, 达到了同功率下CO2激光器和商用全固态 激光器的输出水平, 极大地推动了高功率半导体激 光器从泵浦应用发展到直接应用, 结合其小体积、轻 重量、高转换效率及宽光谱输出等特性, 将在材料加 工、成像探测、医疗、显示等领域获得广泛应用. 在 国防领域, 半导体激光器将作为新一代小型化、轻量 化的激光载荷光源, 装备到车载、机载等机动性强的 作战平台. 目前, 我国在高端半导体激光芯片及合束光源 方面与国外仍有一定差距. 需要进一步提高半导体 激光芯片的功率和光束质量; 攻克万瓦级激光合束 和光纤组束技术; 解决光栅制造关键技术; 亟待联 合国内优势单位进行攻关和突破, 实现高端半导体 激光器产品的自主研发和生产. 图 6 (网络版彩色)基于窄带滤光片的外腔反馈波长锁定结构 Figure 6 (Color online) Structure of feedback cavity with wavelength-locked by the narrowband filter 图 7 (网络版彩色)2 个迷你bar(5 个锥形激光单元)相干合束实验示意图 Figure 7 (Color online) CBC Experimental setup for two mini bar architecture with five MOPA emitters each
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3725 进 展 参考文献 1 Sverdlov B, Pfeiffer H U, Zibik E, et al. Optimization of fiber coupling in ultra-high power pump modules at λ=980 nm. Proc SPIE, 2013, 8605: 860508 2 Walpole J N, Donnelly J P, Taylor P J, et al. Slab-coupled 1.3-μm semiconductor laser with single-spatial large-diameter mode. IEEE Photonics Tech Lett, 2002, 14: 756–758 3 Huang R K, Donnelly J P, Missaggia L J, et al. High brightness slab-coupled optical waveguide lasers. Proc SPIE, 2007, 6485: 64850F 4 Huang R K, Chann B, Missaggia L J, et al. High-power coherent beam combination of semiconductor laser arrays. In: Proceedings of Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference and Photonic Application Systems Technologies. Optical Society of America, 2008 5 Dogana M, Smith G M, Missaggia L J, et al. Dense array slab-coupled optical waveguide laser capable of 500 W/bar. Proc SPIE, 2014, 8965: 89650L 6 Smith G M, Donnelly J P, Missaggia L J, et al. Slab-coupled optical waveguide lasers and amplifiers. Proc SPIE, 2012, 8241: 82410S 7 Schwertfeger S, Wiedmann J, Sumpf B, et al. 7.4 W continuous-wave output power of master oscillator power amplifier system at 1083 nm. Electron Lett, 2006, 42: 346–347 8 Wenzel H, Paschke K, Brox O, et al. 10 W continuous-wave monolithically integrated master-oscillator power-amplifier. Electron Lett, 2007, 43: 160–162 9 Lammert R M, Osowski M L, Elarde V C, et al. High-power single-mode laser diodes with tapered amplifiers. In: Proceedings of IEEE Lasers and Electro-Optics Society. Acapulco: IEEE, 2008. 850–851 10 Spiessberger S, Schiemangk M, Sahm A, et al. Micro-integrated 1 Watt semiconductor laser system with a linewidth of 3.6 kHz. Opt Express, 2011, 19: 7077–7083 11 Feise D, Blume G, Dittrich H, et al. High-brightness 635 nm tapered diode lasers with optimized index guiding. Proc SPIE, 2010, 7583: 75830V 12 Sumpf B, Adamiec P, Zorn M, et al. 650 nm tapered lasers with 1 W maximum output power and nearly diffraction limited beam quality at 500 mW. Proc SPIE, 2008, 6876: 68760M 13 Sumpf B, Adamiec P, Zorn M, et al. Nearly diffraction-limited tapered lasers at 675 nm with 1-W output power and conversion efficiencies above 30%. IEEE Photonics Tech Lett, 2011, 23: 266–268 14 Erbert G, Fricke J, Hülsewede R, et al. 3 W-high brightness tapered diode lasers at 735 nm based on tensile strained GaAsP-QWs. Proc SPIE, 2003, 4995: 29–38 15 Dittmar F, Sumpf B, Fricke J, et al. High-power 808-nm tapered diode lasers with nearly diffraction-limited beam quality of M2 =1.9 at P=4.4 W. IEEE Photonics Tech Lett, 2006, 18: 601–603 16 Fiebig C, Blume G, Kaspari C, et al. 12 W high-brightness single-frequency DBR tapered diode laser. Electron Lett, 2008, 44: 1253–1254 17 Müller A, Zink C, Fricke J, et al. 1030 nm DBR tapered diode laser with up to 16 W of optical output power. Proc SPIE, 2017, 10123: 101231B 18 Sumpf B, Hasler X H, Adamiec P, et al. 12.2 W output power from 1060 nm DBR tapered lasers with narrow spectral line width and nearly diffraction limited beam quality. In: Proceedings of European Conference on Lasers and Electro-Optics 2009 and the European Quantum Electronics Conference. CLEO Europe-EQEC, 2009 19 Winterfeldt M, Crump P, Knigge S, et al. High beam quality in broad area lasers via suppression of lateral carrier ac-cumulation. IEEE Photonics Tech Lett, 2015, 27: 1809–1812 20 Crump P, Winterfeldt M, Decker J, et al. Novel approaches to increasing the brightness of broad area lasers. Proc SPIE, 2016, 9767: 97671L 21 Bachmann A, Lauer C, Furitsch M, et al. Recent brightness improvements of 976 nm high power laser bars. Proc SPIE, 2017, 10086: 1008602 22 Kanskar M, Bao L, Chen Z, et al. Flared oscillator waveguide diodes (FLOW-diodes) enable high brightness fiber-coupled modules. In: Proceedings of the 25th International Semiconductor Laser Conference (ISLC). Kobe: IEEE, 2016 23 Kanskar M, Bao L, Chen Z, et al. Continued improvement in reduced-mode (REM) diodes enable 272 W from 105 μm 0.15 NA beam. Proc SPIE, 2017, 10086: 1008609 24 Ledentsov N N, Shchukin V A. Novel concepts for injection lasers. Opt Eng, 2002, 41: 3193–3203
荸通扳2017年11月第6卷第32期 25 Ledentsov NN, Shchukin V A Novel approaches to semiconductor lasers. Proc SPIE, 2002, 4905: 222-234 26 Maximov M V, Shemyakov Y M. Novikov I l, et al. Narrow vertical beam divergence laser diode based on longitudinal photonic band crystal waveguide Electron Lett, 2003, 39: 1729-1731 27 Maximov M V, Shernyakov Y M, Novikov I l, et al. Low divergence edge-emitting laser with asymmetric waveguide based on one-dimensional photonic crystal. Phys Stat Sol C, 2005. 2: 919-922 28 Novikov I l, Gordeev N Y, Shernyakov Y M, et al. High-power single mode(>l w)continuous wave operation of longitudinal photonic band crystal lasers with a narrow vertical beam divergence. Appl Phys Lett, 2008, 92: 103515 Shchukin V, Ledentsov N, Kalosha V, et al. Modeling of photonic crystal based high power high brightness semiconductor lasers. Proc SPE,2010.7597:75971A Liu L, Qu H W, Liu Y, et al. High-power narrow-vertical-divergence photonic band crystal laser diodes with optimized epitaxial struc ture. Appl Phys Lett. 2014, 105: 231110 31 Rosales R, Kalosha V P, Posilovic K, et al. High brightness photonic band crystal semiconductor lasers in the passive mode locking re- gime. Appl Phys Lett, 2014, 105: 161101 32 Miah M J, Kettler T, Kalosha V P, et al. High temperature operation of 1060-nm high-brightness photonic band crystal lasers with very low astigmatism. J Sel Topics Quantum Electron, 2015, 21: 4900206 33 Rosales R, Roblot J, Kalosha V, et al. 1060-nm high brightness picosecond pulse generation in photonic band crystal lasers. IEEE Pho- tonics Tech Lett. 2016. 28: 2086-2089 64 Wang L J, Tong C Z, Tian S C, et al. High-power ultralow divergence edge-emitting diode laser with circular beam. J Sel Topics Quan tum Electron. 2015. 21: 1501609 35 Fricke J, Bugge F, Ginolas A, et al. High-power 980-nm broad-area lasers spectrally stabilized by surface bragg gratings. IEEE Photonics Tech Lett,2010.22:284-286 36 Paschke K, Spie Berger S, Kaspari C, et al. High-power distributed Bragg reflector ridge-waveguide diode laser with very small spectral linewidth Opt Lett, 2010. 35: 402-404 37 SpieBberger S, Schiemangk M, Wicht A, et al. DBR laser diodes emitting near 1064 nm with a narrow intrinsic linewidth of 2 kHz. Appl ysB,2011,104:813-818 38 Jia P, Chen Y Y, Zhang J W, et al. Broad-stripe single longitudinal mode laser based on metal slots. Opt Commun, 2016, 365: 215-219 39 Erbert G, Fricke J, Knauer A, et al. Design and realization of high-power DFB lasers. Proc SPIE, 2004, 5594: 110-123 40 Klehr A, Wenzel H, Brox O, et al. High-power 894 nm monolithic distributed-feedback laser Opt Express, 2007, 15: 11364 41 Schultz C M. Crump P, Wenzel H, et al. Wide temperature range high power broad area 975nm DFB lasers. In: Proceedings of Confer ence on Lasers and Electro-Optics. Baltimore: Optical Society of America, 2009 42 Kanskar M, He Y. Cai J et al. 50% efficient. >5 W. distributed feedback broad area laser(975 nm). In: Proceedings of Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference and Photonic Applications Systems Technologies. Long Beach: Optical Society of America, 2006 43 Jang S J, Yu JS, Lee Y T. Laterally coupled DFB lasers with self-aligned metal surface grating by holographic lithography. IEEE Pho- tonics Tech Lett. 2008. 20: 514-516 44 Gupta J A Barrios P J, Aers G C, et al. 1550 nm GaInNAsSb distributed feedback laser diodes on GaAs Electron Lett. 2008. 44: 578-579 45 Chen YY, Jia P, Zhang J, et al. Gain-coupled distributed feedback laser based on periodic surface anode canals. Appl Opt, 2015, 54 Qin L, Liu Y Ning Y Q, et al. Emission characteristics of surface second-order metal grating distributed feedback semiconductor lasers Sci Bull,2012,57:2083-2086 47 Hemenway M. Urbanek W, Dawson D, et al. Advances in high-brightness fiber-coupled laser modules for pumping multi-kw Cw fiber lasers. Proc sPie,2017,10086:1008605 48 Kanskar M, Bao L, Chen Z et al. Continued improvement in reduced-mode(REM) diodes enable 272 W from 105 um 0. 15 NA beam OC SPIE,2017,10086:1008609 49 Kasai Y, Yamagatab Y, Kaifuchi Y, et al. High-brightness and high-efficiency fiber-coupled module for fiber laser pump with advanced laser diode. Proc SPIE. 2017. 10086: 1008606 0 Yu H Rossi G, Braglia A, et al. Development of a 300 w 105/0. 15 fiber pigtailed diode module for additive manufacturing applications. OC SPIE,2017,10086:100860A 51 Xu D, Guo Z J, Zhang T J, et al. 600 w high brightness diode laser pumping source. Proc SPIE, 2017, 10086: 100860 52 Timmermann A, Bartoschewski D, Schluter S et al. Intensity increasing up to 4 MW/cm? with BALB's via wavelengths coupling. Proc SPlE,2009,7198:71980X 3726
2017 年 11 月 第 62 卷 第 32 期 3726 25 Ledentsov N N, Shchukin V A. Novel approaches to semiconductor lasers. Proc SPIE, 2002, 4905: 222–234 26 Maximov M V, Shernyakov Y M, Novikov I I, et al. Narrow vertical beam divergence laser diode based on longitudinal photonic band crystal waveguide. Electron Lett, 2003, 39: 1729–1731 27 Maximov M V, Shernyakov Y M, Novikov I I, et al. Low divergence edge-emitting laser with asymmetric waveguide based on one-dimensional photonic crystal. Phys Stat Sol C, 2005, 2: 919–922 28 Novikov I I, Gordeev N Y, Shernyakov Y M, et al. High-power single mode (>1 W) continuous wave operation of longitudinal photonic band crystal lasers with a narrow vertical beam divergence. Appl Phys Lett, 2008, 92: 103515 29 Shchukin V, Ledentsov N, Kalosha V, et al. Modeling of photonic crystal based high power high brightness semiconductor lasers. Proc SPIE, 2010, 7597: 75971A 30 Liu L, Qu H W, Liu Y, et al. High-power narrow-vertical-divergence photonic band crystal laser diodes with optimized epitaxial structure. Appl Phys Lett, 2014, 105: 231110 31 Rosales R, Kalosha V P, Posilovic K, et al. High brightness photonic band crystal semiconductor lasers in the passive mode locking regime. Appl Phys Lett, 2014, 105: 161101 32 Miah M J, Kettler T, Kalosha V P, et al. High temperature operation of 1060-nm high-brightness photonic band crystal lasers with very low astigmatism. J Sel Topics Quantum Electron, 2015, 21: 4900206 33 Rosales R, Roblot J, Kalosha V, et al. 1060-nm high brightness picosecond pulse generation in photonic band crystal lasers. IEEE Photonics Tech Lett, 2016, 28: 2086–2089 34 Wang L J, Tong C Z, Tian S C, et al. High-power ultralow divergence edge-emitting diode laser with circular beam. J Sel Topics Quantum Electron, 2015, 21: 1501609 35 Fricke J, Bugge F, Ginolas A, et al. High-power 980-nm broad-area lasers spectrally stabilized by surface bragg gratings. IEEE Photonics Tech Lett, 2010, 22: 284–286 36 Paschke K, Spießberger S, Kaspari C, et al. High-power distributed Bragg reflector ridge-waveguide diode laser with very small spectral linewidth. Opt Lett, 2010, 35: 402–404 37 Spießberger S, Schiemangk M, Wicht A, et al. DBR laser diodes emitting near 1064 nm with a narrow intrinsic linewidth of 2 kHz. Appl Phys B, 2011, 104: 813–818 38 Jia P, Chen Y Y, Zhang J W, et al. Broad-stripe single longitudinal mode laser based on metal slots. Opt Commun, 2016, 365: 215–219 39 Erbert G, Fricke J, Knauer A, et al. Design and realization of high-power DFB lasers. Proc SPIE, 2004, 5594: 110–123 40 Klehr A, Wenzel H, Brox O, et al. High-power 894 nm monolithic distributed-feedback laser. Opt Express, 2007, 15: 11364 41 Schultz C M, Crump P, Wenzel H, et al. Wide temperature range high power broad area 975nm DFB lasers. In: Proceedings of Conference on Lasers and Electro-Optics. Baltimore: Optical Society of America, 2009 42 Kanskar M, He Y, Cai J, et al. 50% efficient, >5 W, distributed feedback broad area laser (975 nm). In: Proceedings of Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference and Photonic Applications Systems Technologies. Long Beach: Optical Society of America, 2006 43 Jang S J, Yu J S, Lee Y T. Laterally coupled DFB lasers with self-aligned metal surface grating by holographic lithography. IEEE Photonics Tech Lett, 2008, 20: 514–516 44 Gupta J A, Barrios P J, Aers G C, et al. 1550 nm GaInNAsSb distributed feedback laser diodes on GaAs. Electron Lett, 2008, 44: 578–579 45 Chen Y Y, Jia P, Zhang J, et al. Gain-coupled distributed feedback laser based on periodic surface anode canals. Appl Opt, 2015, 54: 8863–8866 46 Qin L, Liu Y, Ning Y Q, et al. Emission characteristics of surface second-order metal grating distributed feedback semiconductor lasers. Sci Bull, 2012, 57: 2083–2086 47 Hemenway M, Urbanek W, Dawson D, et al. Advances in high-brightness fiber-coupled laser modules for pumping multi-kW CW fiber lasers. Proc SPIE, 2017, 10086: 1008605 48 Kanskar M, Bao L, Chen Z, et al. Continued improvement in reduced-mode (REM) diodes enable 272 W from 105 µm 0.15 NA beam. Proc SPIE, 2017, 10086: 1008609 49 Kasai Y, Yamagatab Y, Kaifuchi Y, et al. High-brightness and high-efficiency fiber-coupled module for fiber laser pump with advanced laser diode. Proc SPIE, 2017, 10086: 1008606 50 Yu H, Rossi G, Braglia A, et al. Development of a 300 W 105/0.15 fiber pigtailed diode module for additive manufacturing applications. Proc SPIE, 2017, 10086: 100860A 51 Xu D, Guo Z J, Zhang T J, et al. 600 W high brightness diode laser pumping source. Proc SPIE, 2017, 10086: 1008603 52 Timmermann A, Bartoschewski D, Schlüter S, et al. Intensity increasing up to 4 MW/cm2 with BALB’s via wavelengths coupling. Proc SPIE, 2009, 7198: 71980X
53 VoB M, Meinschien J, Bruns P, et al. High brightness fibre coupled diode lasers of up to 4-kw output power for material processing. Proc SPE,2012,8241:824103 54 Kohler B, Kissel H High-power, high-brightness and low-weight fiber coupled diode laser device. Proc SPIE, 2011, 7918: 791800 55 Kohler B, Unger A, Kissel H, et al. Multi-kw high-brightness fiber coupled diode laser. Proc SPIE, 2013, 8605: 86050B 56 Strohmaier S, Tillkorn C, Olschowsky P, et al. High-power, high-brightness direct-diode LASERS. OPN Optics Photonics News, 2010, 21:25-29 57 Kissel H, Wolf P, Bachmann A. et al. Tailored bars at 976 nm for high-brightness fiber-coupled modules. Proc SPIE, 2017, 10086 100860B 58 Konning T, Kohler B, Wolf P, et al. Optical components for tailoring beam properties of multi-kw diode lasers. Proc SPIE, 2017, 10085 100850G 59 Krause V, Koesters A. Koenig H, et al. Brilliant high-power diode lasers based on broad area lasers. Proc SPIE, 2008, 6876: 687615 60 Malchus J, Krausea V, Koesters A, et al. A 25 kW fiber-coupled diode laser for pumping applications. Proc SPIE, 2014, 8965: 89650B 61 Malchus J, Krause V, Rehmann G, et al. A 40 kw fiber-coupled diode laser for material processing and pumping applications. Proc SPIE 015,9348:934803 62 Decker J, Crump P, Fricke J, et al. 25-W monolithic spectrally stabilized 975 nm minibars for dense spectral beam combining IEEE Photonics Tech Lett. 2015. 27: 1675-1678 63 Witte U, Traub M. Meo A D, et al. Compact 35 um fiber coupled diode laser module based on dense wavelength division multiplexing of NBA mini-bars. Proc SPIE. 2017. 9733: 97330H 64 Unger A, Uthoff R, Stoiber M, et al. Tailored bar concepts for 10 mm-mrad fiber coupled modules scalable to kw-class direct diode la rs. Proc SPIe,2015,9348:934809 65 Witte U, Schneider F, Holly C, et al. kw-class direct diode laser for sheet metal cutting based on commercial pump modules. Proc SPIE, 2017,10086:1008608 66 Heinemann S, Fritsche H, Kruschke B, et al. Compact high brightness diode laser emitting 500 W from a 100 um fiber. PrOc SPIE, 2017. 8605:86050Q 67 Fritsche H, Krusche B, Koch R, et al. High brightness, direct diode laser with kW output power. Proc SPIE, 2014, 8965: 89650G 68 Fabio F, Haro F, Andreas G, et al. Building block diode laser concept for high brightness laser output in the kw range and its applica ns. Proc SPIe,2016.9730:97300G 69 Hengesbach S, Krauch N, Holly C, et al. High-power dense wavelength division multiplexing of multimode diode laser radiation based on volume Bragg gratings Opt Lett, 2013, 38: 3154-3157 70 Daneu V, Sanchez A, Fan TY, et al. Spectral beam combining of a broad-stripe diode laser array in an external cavity. Opt Lett, 2000 25:405-407 71 Chann B, Huang R K, Missaggia L J, et al. Near-diffraction-limited diode laser arrays by wavelength beam combining. Opt Lett, 2005, 30:2104-2100 72 Gopinath J T, Chann B, Fan TY, et al. 1450-nm high-brightness wavelength-beam combined diode laser array Opt Express, 2008, 16: 9405—9410 73 Huang R K. Bien C, James B. et al. Teradiode' s high brightness semiconductor lasers. Proc SPlE, 2016, 9730: 97300C 74 Hecht J Beam combining cranks up the power Laser Focus World, 2012, 48: 41-43 75 Zimer H, Haas M, Ried S, et al. Thin film filter wavelength-locked laser cavity for spectral beam combining of diode laser arrays. In: Proceedings of 2014 IEEE Photonics Conference. San Diego: IEEE. 2014. 230-231 76 Zimer H, Haas M, Nagel S, et al. Spectrally stabilized and combined diode lasers. In: Proceedings of 2015 IEEE High Power Diode La sers and Systems Conference(HPD). Coventry: IEEE, 2015. 31-32 77 Strohmaier S G, Erbert G, Meissner-Schenk A H, et al. kw-class diode laser bars. Proc SPIE. 2017. 10086: 100860C 78 Redmond S M, Creedon K J, Kansky J E Active coherent beam combining of diode lasers. Opt Lett, 2011, 36: 999-1001 79 Schimmel G, Janicot S, Hanna M, et al. Coherent beam combining architectures for high power tapered laser arrays. Proc SPIE, 2017, 10086:1008600 3727
3727 进 展 53 Voß M, Meinschien J, Bruns P, et al. High brightness fibre coupled diode lasers of up to 4-kW output power for material processing. Proc SPIE, 2012, 8241: 824103 54 Köhler B, Kissel H. High-power, high-brightness and low-weight fiber coupled diode laser device. Proc SPIE, 2011, 7918: 79180O 55 Köhler B, Unger A, Kissel H, et al. Multi-kW high-brightness fiber coupled diode laser. Proc SPIE, 2013, 8605: 86050B 56 Strohmaier S, Tillkorn C, Olschowsky P, et al. High-power, high-brightness direct-diode LASERS. OPN Optics Photonics News, 2010, 21: 25–29 57 Kissel H, Wolf P, Bachmann A. et al. Tailored bars at 976 nm for high-brightness fiber-coupled modules. Proc SPIE, 2017, 10086: 100860B 58 Könning T, Köhler B, Wolf P, et al. Optical components for tailoring beam properties of multi-kW diode lasers. Proc SPIE, 2017, 10085: 100850G 59 Krause V, Koesters A, Koenig H, et al. Brilliant high-power diode lasers based on broad area lasers. Proc SPIE, 2008, 6876: 687615 60 Malchus J, Krausea V, Koesters A, et al. A 25 kW fiber-coupled diode laser for pumping applications. Proc SPIE, 2014, 8965: 89650B 61 Malchus J, Krause V, Rehmann G, et al. A 40 kW fiber-coupled diode laser for material processing and pumping applications. Proc SPIE, 2015, 9348: 934803 62 Decker J, Crump P, Fricke J, et al. 25-W monolithic spectrally stabilized 975 nm minibars for dense spectral beam combining. IEEE Photonics Tech Lett, 2015, 27: 1675–1678 63 Witte U, Traub M, Meo A D, et al. Compact 35 µm fiber coupled diode laser module based on dense wavelength division multiplexing of NBA mini-bars. Proc SPIE, 2017, 9733: 97330H 64 Unger A, Uthoff R, Stoiber M, et al. Tailored bar concepts for 10 mm-mrad fiber coupled modules scalable to kW-class direct diode lasers. Proc SPIE, 2015, 9348: 934809 65 Witte U, Schneider F, Holly C, et al. kW-class direct diode laser for sheet metal cutting based on commercial pump modules. Proc SPIE, 2017, 10086: 1008608 66 Heinemann S, Fritsche H, Kruschke B, et al. Compact high brightness diode laser emitting 500 W from a 100 µm fiber. Proc SPIE, 2017, 8605: 86050Q 67 Fritsche H, Krusche B, Koch R, et al. High brightness, direct diode laser with kW output power. Proc SPIE, 2014, 8965: 89650G 68 Fabio F, Haro F, Andreas G, et al. Building block diode laser concept for high brightness laser output in the kW range and its applications. Proc SPIE, 2016, 9730: 97300G 69 Hengesbach S, Krauch N, Holly C, et al. High-power dense wavelength division multiplexing of multimode diode laser radiation based on volume Bragg gratings. Opt Lett, 2013, 38: 3154–3157 70 Daneu V, Sanchez A, Fan T Y, et al. Spectral beam combining of a broad-stripe diode laser array in an external cavity. Opt Lett, 2000, 25: 405–407 71 Chann B, Huang R K, Missaggia L J, et al. Near-diffraction-limited diode laser arrays by wavelength beam combining. Opt Lett, 2005, 30: 2104–2106 72 Gopinath J T, Chann B, Fan T Y, et al. 1450-nm high-brightness wavelength-beam combined diode laser array. Opt Express, 2008, 16: 9405–9410 73 Huang R K, Bien C, James B, et al. Teradiode’s high brightness semiconductor lasers. Proc SPIE, 2016, 9730: 97300C 74 Hecht J. Beam combining cranks up the power. Laser Focus World, 2012, 48: 41–43 75 Zimer H, Haas M, Ried S, et al. Thin film filter wavelength-locked laser cavity for spectral beam combining of diode laser arrays. In: Proceedings of 2014 IEEE Photonics Conference. San Diego: IEEE, 2014. 230–231 76 Zimer H, Haas M, Nagel S, et al. Spectrally stabilized and combined diode lasers. In: Proceedings of 2015 IEEE High Power Diode Lasers and Systems Conference (HPD). Coventry: IEEE, 2015. 31–32 77 Strohmaier S G, Erbert G, Meissner-Schenk A H, et al. kW-class diode laser bars. Proc SPIE, 2017, 10086: 100860C 78 Redmond S M, Creedon K J, Kansky J E. Active coherent beam combining of diode lasers. Opt Lett, 2011, 36: 999–1001 79 Schimmel G, Janicot S, Hanna M, et al. Coherent beam combining architectures for high power tapered laser arrays. Proc SPIE, 2017, 10086: 100860O
荸通扳2017年11月第62卷第32期 Summary for“高功率、高光束质量半导体激光器研究进展 Advances in high power high beam quality diode lasers ZHANG Jun, CHEN Yong Yi2f, QIN Li2f, PENG Hang 2, NING Yong.2& WANG LiJun,2 ry of Luminescence and Applications, Changchun 130033, China ding author, E-mail: penghy(ciompaccn Semiconductor laser enjoys its benefits such as small volume, light weight, long operation life, various selectable wavelength and direct current driving, meanwhile suffers from its beam quality which is making it hard for direct applicdations. Researchers around the world realize that it is beam quality has the same importance as power, and acquiring high power and high beam quality is the key issue in semiconductor laser induxtry. The question of how to improve the beam quality of high power semiconductor lasers is attracting increasing attention from researchers home and abroad. Considering the application fields which require high power high beam quality, such as industry processing and national defense, this paper discussed the research progress on both diode laser unit devices and laser beam combining sources. First of all, the relationships between single laser emitter's structureand themodeof laser units, including lateral mode, transverse mode and longitudinal mode, are analyzed. Lateral mode is the main factor which limits the high beam quality for high power semiconductor lasers. Ridge waveguide is the main method adopted to realize single lateral mode. A method called longitudinal photonic bandgap crystal is introduced to manipulate the transverse mode of a single laser unit, which can acquire large optical near field and high beam quality even in high current input. To control longitude mode, usually to acquire single longitude mode in single semiconductor laser unit, distribute Bragg reflectors and distribute feedback structures using gratings in fabrication is also introduced in this section. And then we summarize the methods and some results of controlling modeusedinternationalresearchers Further more,we introduced the lasers beam technology, including beam shaping and beam combining, considering all conditions of single emitters beam combining, mini bar beam combining, centimeter bar beam combining, laser stacks beam combining and laser systems beam combining. In beam combining technology, we introducted the method of traditional beam combining, including polarization beam combining and wavelength beam combining. Then the method of using dense wavelength division multiplexing with volume Bragg gratings to realize beam combinign is also introduced. Spectrum beam combining method using a Bragg diffractive grating is then introduced, which may realize high beam quality of a single emitters beam spot with a laser bar's optical power. Furthermore, coherent beam combining considering each laser unit's wavelength, polarization and phase to realize high power high intensity farfield is also introduce. Then, the lastest intemational reported of high power, high beam quality diode laser combining sources are introduced, and characteristics of laser beam technology and development trends arediscussed and analyzed. Finally, the developments of high power high beam quality diode lasers are prospected. Right now, our country still have a ch in high quality semiconductor laser chip and be The emiconductor laser chips' power and beam quality needed to be improved. The technology of 10 kw level combining and optical fiber coupling technology is still urged to be acquired. Grating fabrication in optical combining technology and chip fabrication are also needed to be conquered. diode laser, high power high beam quality, laser beam combining doi:10.1360/N972017-00352
2017 年 11 月 第 62 卷 第 32 期 3728 Summary for “高功率、高光束质量半导体激光器研究进展” Advances in high power high beam quality diode lasers ZHANG Jun1,2, CHEN YongYi1,2†, QIN Li1,2†, PENG HangYu1,2*, NING YongQiang1,2 & WANG LiJun1,2 1 Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China; 2 State Key Laboratory of Luminescence and Applications, Changchun 130033, China † Equally contributed to this work * Corresponding author, E-mail: penghy@ciomp.ac.cn Semiconductor laser enjoys its benefits such as small volume, light weight, long operation life, various selectable wavelength and direct current driving, meanwhile suffers from its beam quality which is making it hard for direct applicdations. Researchers around the world realize that it is beam quality has the same importance as power, and acquiring high power and high beam quality is the key issue in semiconductor laser induxtry. The question of how to improve the beam quality of high power semiconductor lasers is attracting increasing attention from researchers home and abroad. Considering the application fields which require high power high beam quality, such as industry processing and national defense, this paper discussed the research progress on both diode laser unit devices and laser beam combining sources. First of all, the relationships between single laser emitter’s structureand themodeof laser units, including lateral mode, transverse mode and longitudinal mode, are analyzed. Lateral mode is the main factor which limits the high beam quality for high power semiconductor lasers. Ridge waveguide is the main method adopted to realize single lateral mode. A method called longitudinal photonic bandgap crystal is introduced to manipulate the transverse mode of a single laser unit, which can acquire large optical near field and high beam quality even in high current input. To control longitude mode, usually to acquire single longitude mode in single semiconductor laser unit, distribute Bragg reflectors and distribute feedback structures using gratings in fabrication is also introduced in this section. And then we summarize the methods and some results of controlling modeusedinternationalresearchers. Further more, we introduced the lasers beam technology, including beam shaping and beam combining, considering all conditions of single emitters beam combining, mini bar beam combining, centimeter bar beam combining, laser stacks beam combining and laser systems beam combining. In beam combining technology, we introducted the method of traditional beam combining, including polarizetion beam combining and wavelength beam combining. Then the method of using dense wavelength division multiplexing with volume Bragg gratings to realize beam combinign is also introduced. Spectrum beam combining method using a Bragg diffractive grating is then introduced, which may realize a high beam quality of a single emitter’s beam spot with a laser bar’s optical power. Furthermore, coherent beam combining considering each laser unit’s wavelength, polarization and phase to realize high power high intensity farfield is also introduce. Then, the lastest international reported of high power, high beam quality diode laser combining sources are introduced, and characteristics of laser beam technology and development trends arediscussed and analyzed. Finally, the developments of high power high beam quality diode lasers are prospected. Right now, our country still have a distance below internal research in high quality semiconductor laser chip and beam combining source. The semiconductor laser chips’ power and beam quality needed to be improved. The technology of 10 kW level beam combining and optical fiber coupling technology is still urged to be acquired. Grating fabrication in optical beam combining technology and chip fabrication are also needed to be conquered. diode laser, high power, high beam quality, laser beam combining doi: 10.1360/N972017-00352