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Optical spin pumping of modulation doped electrons probed by a two-color Kerr rotation technique

H. Hoffmann·G. V. Astakhov·T. Kiessling·W. Ossau·G. Karczewski·T. Wojtowicz·J. Kossut·L. W. Molenkamp
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Abstract

We report on optical spin pumping of modulation electrons in CdTe-based quantum wells with low intrinsic electron density (by 10^10 cm^{-2}). Under continuous wave excitation, we reach a steady state accumulated spin density of about 10^8 cm^{-2}. Using a two-color Hanle-MOKE technique, we find a spin relaxation time of 34 ns for the localized electrons in the nearly unperturbed electron gas. Independent variation of the pump and probe energies demonstrates the presence of additional non-localized electrons in the quantum well, whose spin relaxation time is substantially shorter.

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H. Hoffmann, G. V. Astakhov, T. Kiessling, W. Ossau, G. Karczewski, T. Wojtowicz, J. Kossut, L. W. Molenkamp. 2006-06-15. Optical spin pumping of modulation doped electrons probed by a two-color Kerr rotation technique. https://doi.org/10.1103/physrevb.74.073407

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