Andreev reflection through a quantum dot coupled with two ferromagnets and a superconductor

Article

关键词: JUNCTIONS;    TRANSPORT;    POINT;    MAGNETORESISTANCE;    NANOSTRUCTURES;    SUPERCURRENT;    IMBALANCE;    CONTACT;    METAL;   

DOI  :  10.1103/PhysRevB.65.024516

来源: SCIE

【 摘 要 】

We study the Andreev reflection (AR) in a three-terminal mesoscopic hybrid system, in which two ferromagnets (F-1 and F-2) are coupled to a superconductor (S) through a quantum dot. By using nonequilibrium Green function, we derive a general current formula which allows arbitrary spin polarizations, magnetization orientations, and bias voltages in F-1 and F-2. The formula is applied to study both zero bias conductance and finite bias current. The current conducted by crossed AR involving F-1, F-2, and S is particularly unusual, in which an electron with spin sigma incident from one of the ferromagnets picks up another electron with spin (sigma) over bar from the other one, both enter S and form a Cooper pair. Several special cases are investigated to reveal the properties of AR in this system.

【 授权许可】

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