隧道带间耦合级联新型激光器扩展电流的优化

Optimization on the Expanding Current of Novel Inter-band Tunnel Cascade coupled lasers

隧道带间耦合级联激光器采用 C掺杂生长隧道结 ,由于高浓度 C掺杂层在激光器多个有源区之间分布形成了高电导层 ,增加了注入电流的横向扩展 ,使激光器的性能不能充分发挥出来。我们利用双面电极新型结构可以很好地克服横向电流扩展 ,使级联的激光器保证充分的光输出功率。具体是在常规激光器背面衬底做完全与正面电极相同而对中的电极。当加入电场后 ,使电场完全集中在这两个相对中的电极之间 ,使激光器注入的电流从正面电极完全不扩展地流入到背面衬底电极 ,保证每个有源区都注入相同的电流而保证每个有源区充分的光输出。对 4个有源区级联的激光器光输出功率较常规电极提高 70 %以上 ,输出光功率从 1.6 W提高到 2 .4W,斜率效率提高 70

By use of carbon-doping tunnel junction which has a very high tunnel probability at reverse bias voltage, the distribution of the high concentration carbon-doping layers in multi active layers poses high conductance layers and increases the transverse expanding current, so the laser can not act well. We use a novel double-faced electrode structure to overcome the expanding of the transverse current and ensure the output light power of every cascade lasers. The means is to do a corresponding electrode alike the frontal one on the rear underlay of the conventional laser. When an electric field is put on, it is concentrated in the two electrodes and so the injection current can flow from the frontal electrode to the rear electrode without expanding. This means ensures the equal injection current for every active layer so that there have abundant output light power. To four active layers cascade lasers, the output light power can be promoted 70% by contrast of lasers with conventional electrode. The output light power increases from 1.6 W to 2.4 W. Slope efficiency is 70% more than usual devices.