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arXiv · 1212.5915

Controlled dephasing of an electron interferometer with a path detector at equilibrium

E. Weisz·H. K. Choi·M. Heiblum·Yuval Gefen·V. Umansky·D. Mahalu
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Abstract

Controlled dephasing of electrons, via 'which path' detection, involves, in general, coupling a coherent system to a current driven noise source. However, here, we present a case in which a nearly isolated electron puddle at thermal equilibrium strongly affects the coherence of a nearby electronic interferometer. Moreover, for certain average electron occupations of the puddle, the interferometer exhibits complete dephasing. This robust phenomenon stems from the Friedel Sum Rule, which relates a system's occupation with its scattering phases. The interferometer opens a peeping window into physics of the isolated electron puddle, which cannot be accessed otherwise.

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E. Weisz, H. K. Choi, M. Heiblum, Yuval Gefen, V. Umansky, D. Mahalu. 2012-12-24. Controlled dephasing of an electron interferometer with a path detector at equilibrium. https://doi.org/10.1103/physrevlett.109.250401

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