弯波导吸收区结构1．3μm InGaAsP／InP超辐射发光二极管的设计

^Design of 1. 3μm InGaAsP/InP Superluminescent Diode with A Bent Absorbing Guide Structure

本文用束传播方法（ＢＰＭ）设计了具有弯曲波导吸收区结构１．３μｍＩｎＧａＡｓＰ／ＩｎＰ超辐射发光二极管（ＳＬＤ），分析了不同吸收区长度Ｌａ和弯曲的曲率半径Ｒ对ＳＬＤ特性的影响，给出了直观的结果，并进行了优化设计。在假定吸收区后端面反射率为１，和忽略吸收区内的吸收损耗的条件下，取ｄ＝０．２μｍ，ｗ＝２μｍ，Ｌｐ＝４００μｍ，Ｌａ＝２００μｍ，Ｒ＝５００μｍ，Ｉ＝２００ｍＡ，经吸收区反射耦合回有源区内的光与有源区前端面入射光的强度比率仅为９．５×１０－３。

m InGaAsP/InP superluminescent diodes with a bent absorbing guide structure are designed by the beam propagation method. The different absorbing region length La and bent guide radius R affect the Chsracteristics of SLD.An obvious effect and optimal design are given. Suppose the reflectivity of the back end facet is 1 and the internal losses in the absorbing region are ignored, and d= 0.2μm,w= 2μm,Lp=400μm,La= 200μm, R=500μm,I=200mA,then the ratio between the light energy from the absorbing region that can be recoupled into the active region and the incidence energy from the front and facet of active region is only 9. 5×10-3.