Semiconductor Science and Technology

Coherent manipulation of biexcitonic transitions and other two-pair correlations

V. M. Axt

Published Mar 8, 2004• 5 citations

Abstract

Two-pair correlations are shown to induce dependences of the nonlinear optical response of semiconductors that can be used for a coherent manipulation of the resulting emission. Influences of biexcitonic transitions as well as transitions to two-pair scattering states are discussed within a microscopic density matrix approach. It is shown that the coherent control of biexciton beats is selective with respect to the propagation direction of the emitted signal, in contrast to the control of beats where all beat partners are generated by single photon processes. Furthermore, it is demonstrated that memory structures induced by exciton?exciton scattering states enable coherent manipulations of the excitonic line shape that allow us to estimate lower bounds for the corresponding memory time from experimentally accessible data.

DOI: 10.1088/0268-1242/19/4/073

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