Spin currents in diluted magnetic semiconductors (extended version)

TL;DR

This paper reports the observation of spin currents in diluted magnetic semiconductors, showing how magnetic ion polarization enhances spin-to-charge conversion under terahertz radiation and magnetic fields.

Contribution

It introduces a novel mechanism for spin current generation and conversion in diluted magnetic semiconductors, highlighting the role of magnetic ion polarization and giant Zeeman splitting.

Findings

Pure spin currents are generated by terahertz heating in (Cd,Mn)Te/(Cd,Mg)Te structures.

Magnetic ion polarization significantly enhances spin-to-charge conversion.

External magnetic fields enable control of the resulting electric current.

Abstract

Spin currents resulting in the zero-bias spin separation have been observed in unbiased diluted magnetic semiconductor structures (Cd,Mn)Te/(Cd,Mg)Te. The pure spin current generated due to the electron gas heating by terahertz radiation is converted into a net electric current by application of an external magnetic field. We demonstrate that polarization of the magnetic ion system enhances drastically the conversion due to the spin-dependent scattering by localized Mn(2+) ions and the giant Zeeman splitting.