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arXiv · 1302.5895

Decoherence induced by magnetic impurities in quantum Hall system

V. Kagalovsky·A. L. Chudnovskiy
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Abstract

Scattering by magnetic impurities is known to destroy coherence of electron motion in metals and semiconductors. We investigate the decoherence introduced in a single act of electron scattering by a magnetic impurity in a quantum Hall system. To this end we introduce a fictitious nonunitary scattering matrix $\mathcal{S}$ for electrons that reproduces the exactly calculated scattering probabilities. The strength of decoherence is identified by the deviation of eigenvalues of the product $\mathcal{S}\mathcal{S}^{\dagger}$ from unity. Using the fictitious scattering matrix, we estimate the width of the metallic region at the quantum Hall effect inter-plateau transition and its dependence on the exchange coupling strength and the degree of polarization of magnetic impurities.

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V. Kagalovsky, A. L. Chudnovskiy. 2013-02-24. Decoherence induced by magnetic impurities in quantum Hall system. https://doi.org/10.1134/s1063776113040122

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