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arXiv · 1006.0069

Is the Fano Antiresonance a Necessary Requirement for Circulating Currents in Mesoscopic Interferometers?

Yao Heng Su·Sam Young Cho·Ai Min Chen
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Abstract

Coherent quantum tunneling effects on quantum interference are investigated in electron transport through a mesoscopic interferometer. An evanescent wave tunneling through a potential barrier in one arm can interfere with a propagating wave passing through the other arm of interferometer. It is shown that, even for the same arm lengths, such a quantum interference can induce a circulating current, where Fano antiresonances do not occur in electron transmission. It is found that there exists a critical value of asymmetric arm lengths that gives rise to a Fano antiresonance in electron transmission for the quantum interference between evanescent and propagating waves. We discuss the effects of Fano antiresonances originating from the asymmetric arm lengths on circulating currents.

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Yao Heng Su, Sam Young Cho, Ai Min Chen. 2010-06-01. Is the Fano Antiresonance a Necessary Requirement for Circulating Currents in Mesoscopic Interferometers?. https://arxiv.org/abs/1006.0069

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