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Coherent Population Trapping of Electron Spins in a Semiconductor

Kai-Mei C. Fu·Charles Santori·Colin Stanley·M. C. Holland·Yoshihisa Yamamoto
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Abstract

In high-purity n-type GaAs under strong magnetic field, we are able to isolate a lambda system composed of two Zeeman states of neutral-donor bound electrons and the lowest Zeeman state of bound excitons. When the two-photon detuning of this system is zero, we observe a pronounced dip in the excited-state photoluminescence indicating the creation of the coherent population-trapped state. Our data are consistent with a steady-state three-level density-matrix model. The observation of coherent population trapping in GaAs indicates that this and similar semiconductor systems could be used for various EIT-type experiments.

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Kai-Mei C. Fu, Charles Santori, Colin Stanley, M. C. Holland, Yoshihisa Yamamoto. 2007-06-26. Coherent Population Trapping of Electron Spins in a Semiconductor. https://doi.org/10.1103/physrevlett.95.187405

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