Quantum well width and In composition effects on the operating characteristics of InGaAs/GaAs strained single quantum well diode lasers

摘要

In this work we study the effect of strain on the performance of highly strained InxGa1minus;xAs/GaAs/GaAlAs quantum well lasers (SQWL). We changed the indium concentration and the QW width and found that the threshold current density,Jth, is minimal withxsim;0.4 when the width of the QW is 20 Aring;. Forx=0.3 the minimalJthwas obtained with a 90 Aring; active layer. The best performing laser reported in this work hasJth=68 A/cm2emitting at 1.063 mgr;m with cavity length of 2022 mgr;m. Comparison with GaAs/GaAlAs lasers is possible because both structures have the same optical mode confinement, and the comparison shows that SQWLs have indeed lowerJth, but the improvement inJthwith the strain is not as dramatic as predicted theoretically.