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arXiv · 0805.2715

The Aharonov-Bohm-Casher ring-dot as a flux-tunable resonant tunneling diode

R. Citro·F. Romeo
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Abstract

A mesoscopic ring subject to the Rashba spin-orbit interaction and sequentially coupled to an interacting quantum dot, in the presence of Aharonov-Bohm flux, is proposed as a flux tunable tunneling diode. The analysis of the conductance by means of the nonequilibrium Green's function technique, shows an intrinsic bistability at varying the Aharonov-Bohm flux when 2U > πΓ, U being the charging energy on the dot and Γthe effective resonance width. The bistability properties are discussed in connection with spin-switch effects and logical storage device applications.

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R. Citro, F. Romeo. 2008-05-18. The Aharonov-Bohm-Casher ring-dot as a flux-tunable resonant tunneling diode. https://doi.org/10.1103/physrevb.77.193309

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