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arXiv · 1005.0001

Dynamics and decoherence in the central spin model using exact methods

Michael Bortz·Sebastian Eggert·Christian Schneider·Robert Stubner·Joachim Stolze
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Abstract

The dynamics and decoherence of an electronic spin-1/2 qubit coupled to a bath of nuclear spins via hyperfine interactions in a quantum dot is studied. We show how exact results from the integrable solution can be used to understand the dynamic behavior of the qubit. It is possible to predict the main frequency contributions and their broadening for relatively general initial states analytically, leading to an estimate of the corresponding decay times. Furthermore, for a small bath polarization, a new low-frequency time scale is observed.

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Michael Bortz, Sebastian Eggert, Christian Schneider, Robert Stubner, Joachim Stolze. 2010-10-21. Dynamics and decoherence in the central spin model using exact methods. https://doi.org/10.1103/physrevb.82.161308

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