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Decoherence processes of a quantum two-level system coupled to a fermionic environment

Naoyoshi Yamada·Akimasa Sakuma·Hiroki Tsuchiura
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Abstract

We study decoherence processes of an S = 1/2 localized spin coupled to conduction band electrons in a metal or a semiconductor via an Ising-like interaction. We derive master equations for the density matrix of the localized spin, by tracing out all degrees of freedom in the conduction electron system based on the linked-cluster-expansion technique. It is found that the decoherence occurs more rapidly for the metallic case than for semiconducting case.

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Naoyoshi Yamada, Akimasa Sakuma, Hiroki Tsuchiura. 2007-02-13. Decoherence processes of a quantum two-level system coupled to a fermionic environment. https://doi.org/10.1063/1.2712944

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