Phase and periodicity of Aharonov-Bohm oscillations: effect of channel mixing

P. Singha Deo

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arXiv · cond-mat/9701048

Phase and periodicity of Aharonov-Bohm oscillations: effect of channel mixing

P. Singha Deo

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Abstract

We take a negative delta function impurity in one arm of a quasi one dimensional Aharonov-Bohm ring and demonstrate abrupt phase changes across a quasi bound state of the negative delta function potential. We give a new mechanism for conductance oscillations with the strength of the negative delta potential. We also show that coupling to evanescent modes can result in a $hc/2e$ flux periodicity at certain energies. These observations were made in a recent ingenious experiment by D. Mailly et al [1].

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P. Singha Deo. 1997-01-08. Phase and periodicity of Aharonov-Bohm oscillations: effect of channel mixing. https://arxiv.org/abs/cond-mat/9701048

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