1. Synchronous Spatial Oscillation of Electron- and Mn-Spin Polarizations in Dilute-Magnetic-Semiconductor Quantum Wells under Spin–Orbit Effective Magnetic Fields
- Author
-
Takuma Tsuchiya
- Subjects
Rashba field ,dilute magnetic semiconductors ,General Physics and Astronomy ,FOS: Physical sciences ,Electron ,CdMnTe ,electron-spin precession ,electron-spin polarization ,Mesoscale and Nanoscale Physics (cond-mat.mes-hall) ,s-d interaction ,Physics ,Condensed Matter - Mesoscale and Nanoscale Physics ,Spin polarization ,Condensed matter physics ,Scattering ,Magnetic semiconductor ,Polarization (waves) ,Condensed Matter::Mesoscopic Systems and Quantum Hall Effect ,Mn-spin polarization ,Magnetic field ,Monte Carlo method ,quantum wells ,Ferromagnetism ,impurity Overhauser effect ,Condensed Matter::Strongly Correlated Electrons ,Coherence (physics) - Abstract
In semiconductors, spin-orbit effective magnetic fields, i.e., the Rashba and Dresselhaus fields, are used to control electron-spin polarization. This operation, however, destroys the electron-spin coherence, and the spin polarization is limited to the vicinity of a ferromagnetic source electrode. In this paper, we propose the use of dilute magnetic semiconductors to improve the coherence of spatially oscillating electron-spin polarization. In dilute magnetic semiconductors, the electron-spin polarization near the source electrode dynamically induces the local spin polarization of magnetic impurities through s-d spin-flip scattering. This impurity-spin polarization improves, in turn, the coherence of the electron-spin polarization, and this improved electron-spin polarization induces impurity-spin polarization farther in the adjacent region. Because of this positive feedback, the coherent and synchronized spatial oscillations of electron- and impurity-spin polarizations grow cooperatively. A numerical calculation for a CdMnTe quantum well demonstrates the validity of this mechanism., Comment: 30 pages, 6 figures, 1 table
- Published
- 2012