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Persistent currents in mesoscopic rings with a quantum dot

A. A. Aligia
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Abstract

Using the Anderson model in the Kondo regime, we calculate the persistent current j in a ring with an embedded quantum dot (QD) as a function of the Aharonov-Bohm flux Phi for different ring length L, temperature T and broadening of the conduction states delta . For T=delta =0 and L >> xi, where xi is the Kondo screening length, Lj tends to the value for a non interacting ideal ring, while it is suppressed for a side coupled QD. For any L/xi, Lj is also suppressed when either T or delta increase above a fraction of the level spacing which depends on Phi.

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A. A. Aligia. 2002-06-29. Persistent currents in mesoscopic rings with a quantum dot. https://doi.org/10.1103/physrevb.66.165303

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