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Optical control of spin coherence in singly charged (In,Ga)As/GaAs quantum dots

A. Greilich·R. Oulton·E. A. Zhukov·I. A. Yugova·D. R. Yakovlev·M. Bayer·A. Shabaev·Al. L. Efros·I. A. Merkulov·V. Stavarache·D. Reuter·A. Wieck
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Abstract

Electron spin coherence has been generated optically in n-type modulation doped (In,Ga)As/GaAs quantum dots (QDs) which contain on average a single electron per dot. The coherence arises from resonant excitation of the QDs by circularly-polarized laser pulses, creating a coherent superposition of an electron and a trion state. Time dependent Faraday rotation is used to probe the spin precession of the optically oriented electrons about a transverse magnetic field. Spin coherence generation can be controlled by pulse intensity, being most efficient for (2n+1)pi-pulses.

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A. Greilich, R. Oulton, E. A. Zhukov, I. A. Yugova, D. R. Yakovlev, M. Bayer, A. Shabaev, Al. L. Efros, I. A. Merkulov, V. Stavarache, D. Reuter, A. Wieck. 2006-03-03. Optical control of spin coherence in singly charged (In,Ga)As/GaAs quantum dots. https://doi.org/10.1103/physrevlett.96.227401

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