半导体激光器侧向模式控制技术的研究进展

汪丽杰; 佟存柱; 王延靖; 陆寰宇; 张新; 田思聪; 王立军

doi:10.37188/CO.2022-0143

半导体激光器侧向模式控制技术的研究进展

doi: 10.37188/CO.2022-0143

汪丽杰^{1, 2,},
佟存柱^1, ,,
王延靖¹,
陆寰宇¹,
张新¹,
田思聪¹,
王立军¹

1.
中国科学院长春光学精密机械与物理研究所发光学及应用国家重点实验室,吉林长春 130033
2.
吉光半导体科技有限公司, 吉林长春 130031

基金项目: 国家自然科学基金（No. 62025506, No. 62134008, No. 61790584）；中国科学院青年创新促进会（No. 2021217）；长春市科技计划发展项目（No. 21SH6）

详细信息

作者简介:
汪丽杰（1985—），男，河北石家庄人，副研究员，硕士生导师，2013年于中国科学院长春光学精密机械与物理研究所获得博士学位，主要从事高亮度半导体激光方面的研究。E-mail：wanglijie@ciomp.ac.cn

佟存柱（1976—），男，吉林伊通人，研究员，博士生导师，2005年于中国科学院半导体研究所获得博士学位，主要从事半导体激光方面的研究。E-mail：tongcz@ciomp.ac.cn

中图分类号: TN248.4
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出版历程
- 收稿日期: 2022-06-24
- 修回日期: 2022-07-19
- 网络出版日期: 2022-08-04

Recent advances in lateral mode control technology of diode lasers

1.
State Key Laboratory of Luminescence and Application, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China
2.
Jlight Semiconductor Technology Co., Ltd, Changchun 130031, China

Funds: Supported by National Natural Science Foundation of China (No. 62025506, No. 62134008, No. 61790584); Youth Innovation Promotion Association, CAS (No. 2021217); Changchun City Science and Technology Development Plan (No. 21SH6)

More Information

Corresponding author: tongcz@ciomp.ac.cn

摘要

摘要:
高功率半导体激光器在固体或光纤激光器泵浦、材料加工、激光雷达、空间通讯及国防等领域具有重大需求，但传统器件面临发散角大、光束质量差、亮度低的难题，限制了其直接应用。宽区半导体激光器具有输出功率和转换效率高的优点，但其侧向模式受多种物理效应的影响，高电流下激射模式数很大，导致远场宽度随电流增大迅速展宽，光束质量非常差，成为制约半导体激光亮度提高的关键瓶颈难题。因此，需要对半导体激光器的侧向模式进行控制。本文首先从半导体激光器的侧向模式影响机制出发，分析了其侧向模式特性及光场分布与器件结构的关联关系；接着，介绍了目前主要的侧向模式控制技术，通过抑制高阶模式及侧向远场展宽，实现光束质量的改善及激光亮度的提升。采用先进的侧向模式控制技术，可从芯片层次发展新型的高亮度半导体激光器，有利于拓展半导体激光器应用领域及降低应用成本，具有重要的研究意义。
- 半导体激光 /
- 侧向模式 /
- 光束质量 /
- 高亮度 /
- 低发散角
Abstract:
High power diode lasers are widely used for pumping solid-state lasers and fiber lasers, material processing, laser radars, free-space optical communication, security and defense. However, conventional diode lasers suffer from large far-field divergence angles, poor beam quality and low brightness, which restricts their direct applications. Broad-Area diode Lasers (BALs) can achieve high output power and efficiency. However, their lateral mode is usually influenced by many physical mechanisms, leading to a large number of guided lateral modes at high-power operation. It results in a rapid increase of the far-field width and strongly deteriorated beam quality, limiting the improvement of diode lasers′ brightness. Therefore, the lateral modes should be carefully controlled. In this paper, the factors influencing the diode lasers′ lateral modes are reviewed, and the lateral mode characteristics, optical field distribution and their relations with the device construction are analyzed. Then, the current lateral mode control technologies are described in detail. The beam quality and brightness of the output beam can be enhanced via the suppression of high-order lateral modes and the far-field blooming effect. As a result of advanced lateral mode control, novel high-brightness diode lasers can be developed at the chip level, which is beneficial for developing new diode lasers applications and reducing their system cost.
- diode laser /
- lateral mode /
- beam quality /
- high brightness /
- low divergence angle

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图 1 半导体激光器的侧向模式影响机制

Figure 1. Influence mechanisms of diode laser lateral modes

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图 2 不同阶侧模随电流增大时光场分布变化

Figure 2. Simulated near-field distributions of different order lateral modes as a function of increased current

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图 3 半导体激光器不同阶侧模的近场和远场分布

Figure 3. Calculated (a) near-field and (b) far-field profiles of the lateral mode with different mode orders

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图 4 (a)增益导引、(b)质子注入及(c)二次外延电流阻挡层的半导体激光器侧向电流扩散示意图

Figure 4. Schematic diagram of lateral current spreading for diode lasers utilizing (a) gain-guiding, (b) ion implantation, (c) current-blocking layers after the two-step epitaxial growth

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图 5 空间电流调制（SCM）半导体激光器的结构示意图

Figure 5. Schematic diagram of diode laser with Spatial Current-Modulated (SCM) structure

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图 6 侧向脊波导宽区半导体激光器的结构示意图

Figure 6. Schematic diagram of broad-area diode laser with multiple lateral ridge waveguides

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图 7 基于LLGS结构的布拉格反射波导激光器结构示意图

Figure 7. Schematic diagram of bragg reflection waveguide laser with Ladder Like Groove Structure (LLGS)

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图 8 微条耦合宽区（MSBA）半导体激光器的结构示意图

Figure 8. Schematic diagram of GaSb-based microstripebroad-area (MSBA) lasers

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图 9 GaSb基半导体激光器鱼骨形微光学结构示意图

Figure 9. Schematic diagram of GaSb based diode laser with fish bone micro structures

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图 10 锯齿微结构激光器的结构示意图

Figure 10. Schematic diagram of the laser with sawtooth micro structure

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图 11 箭头型沟槽微光学结构激光器的结构示意图

Figure 11. Schematic diagram of diode laser with arrow-trench micro structure

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图 12 (a)刻蚀微孔的显微镜照片及(b)不同的激光远场形貌

Figure 12. (a) Micrograph of etched micro-holes and (b) different far-field patterns under various currents

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图 13 半导体激光器不同模式的近场分布及损耗剪裁位置

Figure 13. Calculated near-field profiles of the lateral modes with different orders and the loss tailoring placement

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图 14 (a)损耗调控宽区半导体激光器结构示意图；(b)测得的有结构器件和传统宽区结构器件在不同电流下的侧向光束质量对比

Figure 14. (a) Schematic diagram of the loss tailoring BAL; (b)measured lateral beam quality of the structured and unstructured BALs at different currents

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图 15 微结构激光器在室温连续工作下的功率-电流-电压特性曲线

Figure 15. Measured power-current-voltage characteristics of diode lasers with microstructures

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