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arXiv · 0906.2357

Switching of electrical current by spin precession in the first Landau level of an inverted-gap semiconductor

A. R. Akhmerov·C. W. Groth·J. Tworzydlo·C. W. J. Beenakker
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Abstract

We show how the quantum Hall effect in an inverted-gap semiconductor (with electron- and hole-like states at the conduction- and valence-band edges interchanged) can be used to inject, precess, and detect the electron spin along a one-dimensional pathway. The restriction of the electron motion to a single spatial dimension ensures that all electrons experience the same amount of precession in a parallel magnetic field, so that the full electrical current can be switched on and off. As an example, we calculate the magnetoconductance of a p-n interface in a HgTe quantum well and show how it can be used to measure the spin precession due to bulk inversion asymmetry.

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A. R. Akhmerov, C. W. Groth, J. Tworzydlo, C. W. J. Beenakker. 2009-10-27. Switching of electrical current by spin precession in the first Landau level of an inverted-gap semiconductor. https://doi.org/10.1103/physrevb.80.195320

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