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Abstract: The Fano and Kondo cooperated resonant tunneling through a quantum dot interferometer under the perturbation of a rotating magnetic field is investigated theoretically. The spin-polarized current components have been derived generally by employing the Keldysh nonequilibrium Greenʼs function method, through which the charge and spin currents are determined directly. The numerical calculations on spin and charge currents are performed to show the compound features of mesoscopic transport associated with the Kondo, Fano, and Zeeman effects intimately. The induced spin current in the Kondo regime is much different from the one in the non-interacting regime. The spin current is tuned from resonant peak to valley by varying external parameters. [Copyright &y& Elsevier]

Abstract: The commensurate photon-irradiated mesoscopic transport in a strongly correlated quantum dot (QD) embedded Aharonov–Bohm (AB) interferometer has been investigated. We focus our investigation on the dynamic Kondo and Fano cooperated effect affected by the double commensurate MWFs with being an arbitrary integer, where and are the two frequencies of the fields. The general tunneling current formula is derived by employing the nonequilibrium Green''s function technique, and the different photon absorption and emission processes induced nonlinear properties have been studied to compare with the single-field system where . Our numerical calculations are performed for the special cases with two commensurate fields possessing . The Kondo peak can be suppressed to be a Kondo valley for the case where the commensurate number , and the Fano asymmetric structure exhibits in the differential conductance quite evidently. Different commensurate number q contributes different photon absorption and emission effects. However, the conductance for the case of possesses more peaks and heavier asymmetric structure than the situations of . The enhancement of satellite peaks behaves quite differently for the two cases with , and . The asymmetric peak–valley structure is adjusted by the gate voltage, commensurate MWFs, AB flux, source-drain bias, and non-resonant tunneling strength to form novel Fano and Kondo resonant tunneling. [Copyright &y& Elsevier]

Abstract: We have investigated the mesoscopic transport properties of a quantum dot embedded Aharonov–Bohm (AB) interferometer applied with a rotating magnetic field. The spin-flip effect is induced by the rotating magnetic field, and the tunneling current is sensitive to the spin-flip effect. The spin-flipped electrons tunneling from the direct channel and the resonant channel interfere with each other to form spin-polarized tunneling current components. The non-resonant tunneling (direct transmission) strength and the AB phase φ play important roles. When the non-resonant tunneling (background transmission) exists, the spin and charge currents form asymmetric peaks and valleys, which exhibit Fano-type line shapes by varying the source-drain bias voltage, or gate voltage. The AB oscillations of the spin and charge currents exhibit distinct dependence on the magnetic flux and direct tunneling strength. [Copyright &y& Elsevier]