We demonstrate electrical electron spin injection via interband tunneling in ferromagnetic/nonmagnetic semiconductor Esaki diodes. An interband tunnel junction between ferromagnetic p+-(Ga,Mn)As and nonmagnetic n+-GaAs under reverse-bias allows spin-polarized tunneling of electrons from the valence band of (Ga,Mn)As to the conduction band of n+-GaAs. The spin polarization of tunneled electrons is probed by circular polarization of electroluminescence (EL) from an n-GaAs/InGaAs/p-GaAs light emitting structure integrated with the diode. Clear hysteresis loop with +-6.5% remanence is observed in the magnetic-field dependence of the EL polarization at 6 K, below the Curie temperature of (Ga,Mn)As.
@article{arxiv.cond-mat/0110241,
title = {A spin Esaki diode},
author = {Makoto Kohda and Yuzo Ohno and Koji Takamura and Fumihiro Matsukura and Hideo Ohno},
journal= {arXiv preprint arXiv:cond-mat/0110241},
year = {2007}
}
Comments
11pages, 4figures. Submitted Japanese Journal of Applied Physics Pt2 Express Letter