The spin polarization of the electron current in a $p\text{−}(\mathrm{Ga},\mathrm{Mn})\mathrm{As}∕n\text{−}(\mathrm{Al},\mathrm{Ga})\mathrm{As}$ Zener tunnel diode, which is embedded in a light-emitting diode, is studied theoretically. A series of self-consistent simulations determines the charge distribution, the band bending, and the current-voltage characteristics for the entire structure. In order to study the current spin effects the spin dependent tight-binding Hamiltonian is implemented into the Landauer-Büttiker scheme. This dual approach allows us to describe the experimentally observed high magnitude and strong bias dependence of the current spin polarization.

• Received 3 March 2005

DOI:https://doi.org/10.1103/PhysRevB.72.205322