Enhancement of the Quantum-Confined Stark Shift in Disordered, Strained InGaAs/GaAs Single Quantum Wells

Abstract

Theoretical results are presented showing how quantum well disordering modifies the quantum-confined Stark effect in strained InGaAs/GaAs single quantum wells. An error function distribution is used to model the constituent atom composition after interdiffusion. It is shown that for a sufficiently long interdiffusion the exciton Stark shift in the disordered quantum well is greater than in the as-grown quantum well and that the change in electroabsorption near the fundamental absorption edge is larger in the disordered well than in the as-grown well for the same applied electric field. These results demonstrate the potential of using disordering to achieve improved performance in strained InGaAs/GaAs quantum well electroabsorption modulators.