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arXiv · 0909.3406

GHz Spin Noise Spectroscopy in n-Doped Bulk GaAs

Georg M. Müller·Michael Römer·Jens Hübner·Michael Oestreich
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Abstract

We advance spin noise spectroscopy to an ultrafast tool to resolve high frequency spin dynamics in semiconductors. The optical non-demolition experiment reveals the genuine origin of the inhomogeneous spin dephasing in n-doped GaAs wafers at densities at the metal-to-insulator transition. The measurements prove in conjunction with depth resolved spin noise measurements that the broadening of the spin dephasing rate does not result from thermal fluctuations or spin-phonon interaction, as previously suggested, but from surface electron depletion.

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Georg M. Müller, Michael Römer, Jens Hübner, Michael Oestreich. 2010-02-04. GHz Spin Noise Spectroscopy in n-Doped Bulk GaAs. https://doi.org/10.1103/physrevb.81.121202

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