Photon-assisted Andreev tunneling through a mesoscopic hybrid system

Article

关键词: SUPERCONDUCTING QUANTUM POINT;    SINGLE-ELECTRON TRANSISTOR;    MAGNETIC-FIELD DEPENDENCE;    NONLINEAR TRANSPORT;    COULOMB-BLOCKADE;    DOT;    SCATTERING;    ISLAND;    REFLECTION;    JUNCTIONS;   

DOI  :  10.1103/PhysRevB.59.13126

来源: SCIE

【 摘 要 】

The electron tunneling through a mesoscopic hybrid system, a normal-metal-quantum-dot-superconductor (N-QD-S) system where the intradot Coulomb interaction is neglected, in the presence of the time-varying external fields, has been investigated. By using the nonequilibrium Green-function method, the time-dependent current j(L)(t) and the average current < j(t)> are derived. The photon-assisted Andreev tunneling (PAAT) and the normal photon-assisted tunneling (PAT) are studied in detail. In the case of h omega vs the gate voltage exhibits a series of equal-interval PAAT peaks, with negative peaks on the left-hand side and positive peaks on the right-hand side of the original resonant peak in the absence of the external fields. This is very different from the N-QD-N system. While for h omega>Delta, various PAT processes cause a rather complicated dependence of the current on the gate voltage. In addition, the current-bias-voltage characteristics become more complicated: each Andreev reflection peak is split into side-band peaks and each current plateau is split into substep plateaus. [S0163-1829(99)02819-2].

【 授权许可】

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