Driving a pure spin current from nuclear-polarization gradients

A pure spin current is predicted to occur when an external magnetic field and a linearly inhomogeneous spinonly 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.

Automated summary

A pure spin current can be controlled by an external magnetic field and a linearly inhomogeneous spin-only field under specific conditions. This phenomenon can be validated through classical models and optical experiments.