Journal of Applied Physics

Kerr nonlinearity in a driven two-subband system in a semiconductor quantum well

Spyridon G. Kosionis, A. F. Terzis, Emmanuel Paspalakis

Published Apr 15, 2011• 23 citations

Abstract

We study theoretically the Kerr nonlinearity of a probe field in the presence of a near resonant pump field in a two-subband system in a semiconductor quantum well structure. In our study we take into account the effects of electron–electron interactions and consider the interaction of the two-subband system with rectangular electromagnetic fields. For the description of the system dynamics we use the nonlinear differential equations of the density matrix elements for the several nonlinear optical processes, under the rotating wave approximation. These equations are solved numerically for a GaAs/AlGaAs quantum well structure. We show that the Kerr nonlinearity of a driven two-subband system can be significantly dependent on the frequency and the intensity of the pump field and on electron sheet density.

DOI: 10.1063/1.3561484

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