Study of the electronic fundamental transition of zincblende InN/InGaN quantum wells

Abstract

In this work we calculate the transition energy from the first level of holes to the first level of electrons ( 1 h – 1 e ) for cubic InN / In x Ga 1 - x N quantum wells. We employ the empirical tight binding approach with a sp 3 s * orbital basis, nearest neighbors interactions and the spin–orbit coupling, together with the surface Green function matching method. Our tight binding parameters give a value of 0.65 eV for the InN gap and 3.3 eV for GaN. For the In x Ga 1 - x N alloy we use the virtual crystal approximation. We study the transition energy behavior varying the well width for concentrations x = 0.2 , 0.5, and 0.8. For the calculations, we use two values of the valence band offset: 30 % and 50 % . We take into account the strain in the well, due to the different lattice constants between the well and the barrier.