Zeeman ratchets: Rectification of spin current via magnetic fields
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چکیده
We investigate the possibility of creating directed spin-polarized currents in a two-dimensional electron gas (2DEG) subject to an inhomogeneous magnetic field and an external adiabatic driving. We thereby generalize concepts of quantum charge ratchets to the case with spin. Due to the Zeeman term in the Hamiltonian, spin-up and -down electrons experience different effective potentials, which can be tailored to achieve net spin currents without corresponding charge currents. We consider ballistic, coherent transport in waveguides defined in a 2DEG, where the magnetic field modulation is induced by ferromagnetic stripes on top of the 2DEG. PACS numbers: 72.25.Dc, 73.40.Ei, 71.70.Ej Submitted to: New J. Phys. Zeeman ratchets: Rectification of spin current via magnetic fields 2
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تاریخ انتشار 2008