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Vanishing environment-induced decoherence

Yong-Cheng Ou·Heng Fan
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Abstract

For a central system uniformly coupled to a XY spin-1/2 bath in a transverse field, we explicitly calculate the Loschmidt echo(LE) to characterize decoherence quantitatively. We find that the anisotropy parameter $γ$ affects decoherence of the central system sensitively when $γ\in [0,1]$% , in particular, the LE becomes unit without varying with time when $γ=0 $, implying that environment-induced decoherence vanishes . Some other cases in which the LE is unit are discussed also.

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Yong-Cheng Ou, Heng Fan. 2006-08-07. Vanishing environment-induced decoherence. https://doi.org/10.1088/1751-8113/40/10/014

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