Theoretical gain in compressive and tensile strained InGaAs/InGaAsP quantum wells

Abstract

In this letter, we report theoretical predictions of gain in strained 40 Å InGaAs/InGaAsP quantum wells, using a finite barrier valence band mixing analysis to determine the complicated valence subband structure under compressive strain, no strain, and tensile strain. We first illustrate the dramatic effects that strain can have on the valence subband structure. We then show that these changes lead to dramatic alterations in the optical gain of the quantum well as a function of carrier density. Example gain curves are given for three different indium mole fractions. Finally, to observe the effects of strain in a more continuous fashion, we plot theoretical transparency values for carrier density and differential gain as a function of indium mole fraction in the well.