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Andreev reflection resonant tunneling through a precessing spin

Xiufeng Cao·Yaoming Shi·Xiaolong Song·Hao Chen
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Abstract

We investigate Andreev reflection (AR) resonant tunneling through a precessing spin which is coupled to a normal metallic lead and a superconducting lead. The formula of the AR conductance at zero temperature is obtained as a function of chemical potential and azimuthal angle of the spin precessing by using the nonequilibrium Green function method. It is found that as the local spin precesses in a weak external magnetic field at Larmor frequency $ω_l$, the AR tunneling conductance exhibits an oscillation at the frequency $2ω_l$ alone. The amplitude of AR conductance oscillation enhances with spin-flip tunneling coupling increasing. The study also shows that spin-orbit interaction in tunneling barriers is crucial for the oscillations of AR conductance. The effect of spin-flip tunneling coupling caused by spin-orbit interaction and local spin precessing on resonant behavior of the AR conductance are examined.

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Xiufeng Cao, Yaoming Shi, Xiaolong Song, Hao Chen. 2004-09-11. Andreev reflection resonant tunneling through a precessing spin. https://doi.org/10.1016/j.physleta.2004.05.009

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