理论研究电流注入对垂直腔面发射激光器多横模行为的影响

从包含时空变量的速率方程出发,针对弱折射率导引垂直腔面发射激光器(VCSELs),利用空间积分法分析了典型电注入参数对VCSELs多横模行为的影响,在不降低模型准确性的前提下提高了仿真效率。仿真结果表明,注入盘孔径和注入环越小、注入强度越低以及电流扩散越弱时,VCSELs更易实现单横模工作;反之,VCSELs高阶横模开始出现并呈现较强的模式竞争,引发了载流子空间烧孔效应,并导致基模强度降低。进一步得出,在环形注入方式下,高阶模式更容易出现且彼此间的竞争较盘形注入时强。

Theoretical investigation on influence of injection current on multi-transverse-mode behaviors of VCSELs

Basing on the spatio-temporal rate equation,the injection parameters dependences of the multi-transverse-mode behaviors of weakly index guiding vertical-cavity surface-emitting lasers(VCSELs) were investigated by integrating the spatially dependent parts.This method improved the simulation efficiency without degrading the accuracy of the model.Simulation results indicate that VCSELs with small disk injection radius,small injection ring,low bias current,and weakly current spreading exhibit better single-mode characteristics.Contrarily, with the increase of these parameters,the higher-order transverse modes begin to emergence and exhibit strong competitions,moreover,the main mode becomes weaker accordingly,which originates from the spatial hole burning.Compared with disk-contact case,the high-order transverse modes under ring-contact appear more easily and exhibit stronger competitions.