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Persistent spin and charge currents and magnification effects in open ring conductors subject to Rashba coupling

R. Citro·F. Romeo
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Abstract

We analyze the effect of Rashba spin-orbit coupling and of a local tunnel barrier on the persistent spin and charge currents in a one-dimensional conducting Aharonov-Bohm (AB) ring symmetrically coupled to two leads. First, as an important consequence of the spin-splitting, it is found that a persistent spin current can be induced which is not simply proportional to the charge current. Second, a magnification effect of the persistent spin current is shown when one tunes the Fermi energy near the Fano-type antiresonances of the total transmission coefficient governed by the tunnel barrier strength. As an unambiguous signature of spin-orbit coupling we also show the possibility to produce a persistent pure spin current at the interference zeros of the transmittance. This widens the possibilities of employing mesoscopic conducting rings in phase-coherent spintronics applications.

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R. Citro, F. Romeo. 2007-01-18. Persistent spin and charge currents and magnification effects in open ring conductors subject to Rashba coupling. https://doi.org/10.1103/physrevb.75.073306

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