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Quantum spin pumping with adiabatically modulated magnetic barrier's

Ronald Benjamin·Colin Benjamin
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Abstract

A quantum pump device involving magnetic barriers produced by the deposition of ferro magnetic stripes on hetero-structure's is investigated. The device for dc- transport does not provide spin-polarized currents, but in the adiabatic regime, when one modulates two independent parameters of this device, spin-up and spin-down electrons are driven in opposite directions, with the net result being that a finite net spin current is transported with negligible charge current. We also analyze our proposed device for inelastic-scattering and spin-orbit scattering. Strong spin-orbit scattering and more so inelastic scattering have a somewhat detrimental effect on spin/charge ratio especially in the strong pumping regime. Further we show our pump to be almost noiseless, implying an optimal quantum spin pump.

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Ronald Benjamin, Colin Benjamin. 2003-12-09. Quantum spin pumping with adiabatically modulated magnetic barrier's. https://doi.org/10.1103/physrevb.69.085318

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