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arXiv · 1004.5279

Spin-Orbit Based Coherent Spin Ratchets

Matthias Scheid·Dario Bercioux·Klaus Richter
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Abstract

The concept of ratchets, driven asymmetric periodic structures giving rise to directed particle flow, has recently been generalized to a quantum ratchet mechanism for spin currents mediated through spin-orbit interaction. Here we consider such systems in the coherent mesoscopic regime and generalize the proposal of a minimal spin ratchet model based on a non-interacting clean quantum wire with two transverse channels by including disorder and by self-consistently treating the charge redistribution in the nonlinear (adiabatic) ac-driving regime. Our Keldysh-Green function based quantum transport simulations show that the spin ratchet mechanism is robust and prevails for disordered, though non-diffusive, mesoscopic structures. Extending the two-channel to the multi-channel case does not increase the net ratchet spin current efficiency but, remarkably, yields a dc spin transmission increasing linearly with channel number.

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Matthias Scheid, Dario Bercioux, Klaus Richter. 2010-04-29. Spin-Orbit Based Coherent Spin Ratchets. https://doi.org/10.1016/j.chemphys.2010.05.001

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