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arXiv · 2208.03414

Driving a pure spin current from nuclear-polarization gradients

Nicholas J. Harmon·Michael E. Flatté
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Abstract

A pure spin current is predicted to occur when an external magnetic field and a linearly inhomogeneous spin-only field are appropriately aligned. Under these conditions (such as originate from nuclear contact hyperfine fields that do not affect orbital motion) a linear, spin-dependent dispersion for free electrons emerges from the Landau Hamiltonian. The result is that spins of opposite orientation flow in opposite directions giving rise to a pure spin current. A classical model of the spin and charge dynamics reveals intuitive aspects of the full quantum mechanical solution. We propose optical orientation or electrical polarization experiments to demonstrate this outcome.

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Nicholas J. Harmon, Michael E. Flatté. 2022-08-06. Driving a pure spin current from nuclear-polarization gradients. https://doi.org/10.1103/physrevb.106.054207

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