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Dephasing of Aharonov-Bohm oscillations in a mesoscopic ring with a magnetic impurity

Sandeep K. Joshi·Debendranath Sahoo·A. M. Jayannavar
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Abstract

We present a detailed analysis of the Aharonov-Bohm interference oscillations manifested through transmission of an electron in a mesoscopic ring with a magnetic impurity atom inserted in one of its arms. The electron interacts with the impurity through the exchange interaction leading to exchange spin-flip scattering. Transmission in the spin-flipped and spin-unflipped channels are explicitly calculated. We show that the spin-flipper acts as a dephasor in spite of absence of any inelastic scattering. The spin-conductance (related to spin-polarized transmission coefficient) is asymmetric in the flux reversal as opposed to the two probe conductance which is symmetric under flux reversal.

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Sandeep K. Joshi, Debendranath Sahoo, A. M. Jayannavar. 2000-07-26. Dephasing of Aharonov-Bohm oscillations in a mesoscopic ring with a magnetic impurity. https://arxiv.org/abs/cond-mat/0007414

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