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Photorefractive Effects, Materials, and Devices

Exciton Induced Phase Coherent Photorefraction in ZnSe Single Quantum Wells

Hans Peter Wagner, Suvranta K. Tripathy

Published Jan 1, 2005• 0 citations
Publisher

Abstract

We investigate an exciton resonant phase coherent photorefractive effect in ZnSe single quantum wells using ultrashort light pulses. The microscopic origin of the observed effect is attributed to the formation of an electron grating that is induced by the interference of coherent excitons. The coherent nature of this effect can be used to preserve phase and polarization of incident light fields that do not overlap in time.

DOI
10.1364/pemd.2005.8

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We investigate an exciton resonant phase coherent photorefractive effect in ZnSe single quantum wells using ultrashort light pulses. The microscopic origin of the observed effect is attributed to the formation of an electron grating that is induced by the interference of coherent excitons. The coherent nature of this effect can be used to preserve phase and polarization of incident light fields that do not overlap in time.
We observe an efficient phase coherent photorefractive effect in ZnSe single quantum wells for ultrashort light pulses resonant to the excitonic transition. The effect is attributed to the formation of an electron grating in the quantum well induced by the interference of coherent excitons that preserve phase and polarization of the incident light fields. All characteristic features of the diffracted signal are explained and reproduced by numerical calculations that are based on the optical Bloch equations for a three-level system.
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