The spin depolarization of drifting electrons in a n-type doped GaAs bulk semiconductor is studied, in a wide range of lattice temperature (40 K < TL < 300 K) and doping density (10^{13} cm^{−3} < n < 10^{16} cm^{−3}), by adopting a semiclassical Monte Carlo approach. The effect of the mechanism of Dyakonov-Perel (DP) on the spin depolarization of the conduction electrons is analyzed as a function of the amplitude of a static electric field, ranging between 0.1 and 6 kV cm^{−1}, by considering the spin dynamics of electrons in both the Γ-valley and the upper L-valleys of the semiconductor. Moreover, the role of the electron-electron scattering mechanism in the suppression of DP spin relaxation is discussed. For high values of the electric field, the strong spin–orbit coupling of electrons in the Γ-valleys significantly reduces the average spin polarization lifetime, but, unexpectedly, for field amplitudes greater than 2.5 kV cm^{−1}, the spin lifetime increases with the lattice temperature. Our numerical findings are validated by a good agreement with the available experimental results and with calculations recently obtained on different semiconductor structures.
Spezia, S., Persano Adorno, D., Pizzolato, N., Spagnolo, B. (2011). RELAXATION OF ELECTRON SPIN DURING FIELD TRANSPORT IN GaAs BULKS.
RELAXATION OF ELECTRON SPIN DURING FIELD TRANSPORT IN GaAs BULKS
SPEZIA, Stefano;PERSANO ADORNO, Dominique;PIZZOLATO, Nicola;SPAGNOLO, Bernardo
2011-01-01
Abstract
The spin depolarization of drifting electrons in a n-type doped GaAs bulk semiconductor is studied, in a wide range of lattice temperature (40 K < TL < 300 K) and doping density (10^{13} cm^{−3} < n < 10^{16} cm^{−3}), by adopting a semiclassical Monte Carlo approach. The effect of the mechanism of Dyakonov-Perel (DP) on the spin depolarization of the conduction electrons is analyzed as a function of the amplitude of a static electric field, ranging between 0.1 and 6 kV cm^{−1}, by considering the spin dynamics of electrons in both the Γ-valley and the upper L-valleys of the semiconductor. Moreover, the role of the electron-electron scattering mechanism in the suppression of DP spin relaxation is discussed. For high values of the electric field, the strong spin–orbit coupling of electrons in the Γ-valleys significantly reduces the average spin polarization lifetime, but, unexpectedly, for field amplitudes greater than 2.5 kV cm^{−1}, the spin lifetime increases with the lattice temperature. Our numerical findings are validated by a good agreement with the available experimental results and with calculations recently obtained on different semiconductor structures.
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