注入电流引起质子轰击VCSEL中的模式竞争

为了分析质子轰击垂直腔面发射激光器(VCSEL)中注入电流引起的激光模式竞争过程,在三维空间中对VCSEL激射后光电热进行了研究。给出仿真光电热的方程之后,在室温连续工作条件下,对电流孔半径r为4μm、阈值电流Ith为4.5 m A的VCSEL进行自洽求解。当注入电流Iin分别为5.0,5.5,6.0 m A时,得到了对应的外加电压和输出光功率,并绘制了VCSEL的电势、注入电流、载流子、光场和热场的空间分布,给出了连续工作下输出光功率随注入电流变化的曲线。仿真结果表明:随着注入VCSEL中的电流增加,电流密度增大,激光的横向基模和横向一阶模式同时增强。横向一阶模式增加的强度及扩展的范围大于横向基模,激光输出能量逐渐向横向一阶模式过渡,横向模式竞争的同时产生载流子空间烧孔,因此在电流孔半径r≥4μm的VCSEL中,连续工作激光模式不稳定。

Mode Competition in The Proton Implanted VCSEL by Injected Current

In order to present the process of mode competition with increasing injected current in the proton-implanted vertical cavity surface emitting laser (VCSEL), the electric field, carrier, optical and temperature in its lasing were studied in the three dimensions. The opto-electro-thermal self-consistent simulation for the proton-implanted VCSEL under CW operation at room temperature was given after the equations for electric field, carrier, optical and temperature were shown. The voltage electrode and out-put power were obtained in the proton-implanted VCSEL with current aperture radius r=4 mm and thresh-old injected current Ith=4. 5 mA under the injected current Iin =5. 0, 5. 5, 6. 0 mA, respectively. The distributions of electric field, carrier, optical and temperature were obtained in the continuous wave pro-ton-implanted VCSEL. The dependent of the output power on the injected current in proton-implanted VCSEL was also derived. The results show that the injected current density is improved and expanded re-spectively with the increasing of the injected current. The first order transverse mode increases higher than the transverse fundamental mode while the two laser transverse modes are both improved. The output energy is gradual transition to the first order transverse mode. The space burn for carrier in the activity region is found as the mode competition. The laser transverse mode in continuous wave operation for pro-ton-implanted VCSEL with current confinement radius r≥4 mm is unstable.