Spin conductance in ferromagnet/quantum dot/superconductor junctions

doi:10.7523/j.issn.2095-6134.2014.01.004

Abstract

Abstract:

We analyze the spin transport in a ferromagnet/quantum dot/superconductor junction by assuming spin-flip interaction on the quantum dot. The nonequilibrium Green's function method is employed to calculate the tunneling spin current and spin conductance. It is shown that the spin conductance depends sensitively on the orientation of exchange field in the ferromagnet, leading to a controllable giant spin tunneling magnetoresistance effect, even in the moderate temperature and spin polarization regime.

Key words: intradot spin-flip interaction, same-spin-band Andreev reflection, giant spin tunneling magnetoresistance

CLC Number:

O469

NING Wenting, JIN Biao. Spin conductance in ferromagnet/quantum dot/superconductor junctions[J]. , 2014, 31(1): 17-23.

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