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arXiv · 1001.1465

Spin-dependent pump current and noise in an adiabatic quantum pump based on domain walls in a magnetic nanowire

Rui Zhu·Jamal Berakdar
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Abstract

We study the pump current and noise properties in an adiabatically modulated magnetic nanowire with double domain walls (DW). The modulation is brought about by applying a slowly oscillating magnetic and electric fields with a controllable phase difference. The pumping mechanism resembles the case of the quantum dot pump with two-oscillating gates. The pump current, shot noise, and heat flow show peaks when the Fermi energy matches with the spin-split resonant levels localized between the DWs. The peak height of the pump current is an indicator for the lifetime of the spin-split quasistationary states between the DWs. For sharp DWs, the energy absorption from the oscillating fields results in side-band formations observable in the pump current. The pump noise carries information on the correlation properties between the nonequilibrium electrons and the quasi-holes created by the oscillating scatterer. The ratio between the pump shot noise and the heat flow serves as an indicator for quasi-particle correlation.

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Rui Zhu, Jamal Berakdar. 2010-01-10. Spin-dependent pump current and noise in an adiabatic quantum pump based on domain walls in a magnetic nanowire. https://doi.org/10.1103/physrevb.81.014403

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