Tuesday, July 24, 2012

1207.5404 (Henri Saarikoski et al.)

Spin transmission control in helical magnetic fields    [PDF]

Henri Saarikoski, Tobias Dollinger, Klaus Richter
We calculate spin transport in two-dimensional waveguides in the presence of spatially modulated Zeeman-split energy bands. We show that in a regime where the spin evolution is predominantly adiabatic the spin backscattering rate can be tuned via diabatic Landau-Zener transitions between the spin-split bands [C. Betthausen et. al., Science 337, 324 (2012)]. This mechanism is tolerant against spin-independent scattering processes. Completely spin-polarized systems show full spin backscattering, and thus current switching. In partially spin-polarized systems a spatial sequence of Landau-Zener transition points enhances the resistance modulation via reoccupation of backscattered spin-polarized transport modes. We discuss a possible application as a spin transistor.
View original: http://arxiv.org/abs/1207.5404

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