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Coherent backscattering from a quantum dot is insensitive to the Ehrenfest time

A. Tajic·J. Tworzydlo·C. W. J. Beenakker
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Abstract

This paper was withdrawn by the authors. The purpose of this paper was to provide conclusive evidence for the Ehrenfest-time-independence of weak localization, by means of a computer simulation of the coherent backscattering peak on very large systems. (Two orders of magnitude larger than we could reach in cond-mat/0405122 by studying weak localization directly.) We have decided to withdraw this paper, after Piet Brouwer convinced us that the one-to-one correspondence between weak localization and coherent backscattering can not be relied upon. For example, a reflection matrix with one half of its eigenvalues equal to 0 and the other half equal to 1 (hence without weak localization) would still show a coherent backscattering peak in a basis that is randomly related to its eigenbasis.

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A. Tajic, J. Tworzydlo, C. W. J. Beenakker. 2004-06-28. Coherent backscattering from a quantum dot is insensitive to the Ehrenfest time. https://arxiv.org/abs/cond-mat/0406271

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