Reduced threshold current in (111)B grown InGaAs/AlGaAs laser diodes: The positive role of piezoelectric effect

摘要

The authors demonstrate that (111)B grown InGaAs/AlGaAs laser diodes outperform their (100) counterparts, in terms of lower threshold currents observed for all temperature and cavity lengths tested. A low temperature threshold current density as low as 15 A/cm~2 has been observed in (111)B grown devices, whereas identical (100) laser diodes exhibited threshold in the range of 30-40 A/cm~2. The comparison of experimental findings with a Poisson-Schrodinger self-consistent model reveals that the improved performance of the (111)B devices is attributed to the piezoelectric field present in the (111)B In_(0.1)Ga_(0.9)As active quantum well as well as to the different heavy hole effective masses in the (111)B configuration.