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arXiv · 1101.4422

Electron-nuclear dynamics in a quantum dot under non-unitary electron control

Edwin Barnes·Sophia E. Economou
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Abstract

We introduce a method for solving the problem of an externally controlled electron spin in a quantum dot interacting with host nuclei via the hyperfine interaction. Our method accounts for generalized (non-unitary) evolution effected by external controls and the environment, such as coherent lasers combined with spontaneous emission. As a concrete example we develop the microscopic theory of the dynamics of nuclear-induced frequency focusing, as first measured in Science 317, 1896 (2007); we find that the nuclear relaxation rates are several orders of magnitude faster than those quoted in that work.

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Edwin Barnes, Sophia E. Economou. 2011-06-27. Electron-nuclear dynamics in a quantum dot under non-unitary electron control. https://doi.org/10.1103/physrevlett.107.047601

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