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تسجيل مستخدم جديدThe Aharonov-Bohm-Casher ring-dot as a flux-tunable resonant tunneling diode
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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 Greens function technique, shows an intrinsic bistability at varying the Aharonov-Bohm flux when 2U > pi Gamma, U being the charging energy on the dot and Gamma the effective resonance width. The bistability properties are discussed in connection with spin-switch effects and logical storage device applications.
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re than 50% modulation are observed in the conductance. The tuning via in-plane gates allows to study the Aharonov-Bohm effect in the whole range from the open ring to the Coulomb-blockade regime.
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