1.55μm AlGaInAs/InP小发散角量子阱激光器的仿真和制备（英文）

Simulation and fabrication of 1. 55 μm AlGaInAs/InP quantum well lasers with low beam divergence

理论仿真和实验制备了AlGaInAs/InP材料1.55 μm小发散角量子阱激光器.为了扩展近场光场并减小内损耗,将一个非对称模式扩展层插入到外延结构的下盖层当中.仿真结果表明,该模式扩展层除了少量增加激光器阈值电流以外,在不影响激光器其它性能的情况下能显著减小激光器的垂直远场发散角.实验结果与理论仿真高度吻合.成功制备出脊宽4 μm,腔长1 000 μm的脊波导小发散角激光器.在端面未镀膜的情况下,该激光器阈值电流为56 mA,输出功率为17.38 mw@120 mA,斜率效率可以达到0.272 W/A.实验测得垂直远场发散角为29.6°,相比较传统激光器减小了约35.3%.

1.55 μm AlGaInAs/InP quantum well lasers with low beam divergence have been theoretically designed and experimentally fabricated. An asymmetrical mode expand layer (MEL) was inserted in lower cladding to expand near field intensity distribution and decrease internal loss. Simulation results showed that the use of MEL didn’t influence the laser performance negatively but dramatically decreased the vertical beam divergence at the cost of slightly increase of threshold current. And the experiment results showed high agreement to it. With a 4 μm-wide and 1 000 μm-long ridge waveguide laser with MEL, the threshold current and output power of single facet without coating is 56 mA and 17.38 mw@120 mA, and the slope efficiency is 0.272 W/A. The vertical beam divergence is 29.6° and decreases about 35.3% compared to that of typical lasers.