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Adiabatic spin pumping through a quantum dot with a single orbital level

Tomosuke Aono
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Abstract

We investigate an adiabatic spin pumping through a quantum dot with a single orbital energy level under the Zeeman effect. Electron pumping is produced by two periodic time dependent parameters, a magnetic field and a difference of the dot-lead coupling between the left and right barriers of the dot. The maximum charge transfer per cycle is found to be $e$, the unit charge in the absence of a localized moment in the dot. Pumped charge and spin are different, and spin pumping is possible without charge pumping in a certain situation. They are tunable by changing the minimum and maximum value of the magnetic field.

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Tomosuke Aono. 2002-11-06. Adiabatic spin pumping through a quantum dot with a single orbital level. https://doi.org/10.1103/physrevb.67.155303

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