Noise-induced phase transition in the electronic Mach-Zehnder interferometer

Ivan P. Levkivskyi; Eugene V. Sukhorukov

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arXiv · 0903.3349

Noise-induced phase transition in the electronic Mach-Zehnder interferometer

Ivan P. Levkivskyi·Eugene V. Sukhorukov

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Abstract

We consider dephasing in the electronic Mach-Zehnder interferometer strongly coupled to current noise created by a voltage biased quantum point contact (QPC). We find the visibility of Aharonov-Bohm oscillations as a function voltage bias and express it via the cumulant generating function of noise. In the large-bias regime, high-order cumulants of current add up to cancel the dilution effect of a QPC. This leads to an abrupt change in the dependence of the visibility on voltage bias which occurs at the QPC's transparency T=1/2. Quantum fluctuations in the vicinity of this point smear out the sharp transition.

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Ivan P. Levkivskyi, Eugene V. Sukhorukov. 2009-03-19. Noise-induced phase transition in the electronic Mach-Zehnder interferometer. https://arxiv.org/abs/0903.3349

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