Carrier-impurity spin transfer dynamics in paramagnetic II-VI diluted magnetic semiconductors in the presence of a wave-vector-dependent magnetic field

Abstract

Quantum kinetic equations of motion for carrier and impurity spins in paramagnetic II-VI diluted magnetic semiconductors in a $\mathbf{k}$-dependent effective magnetic field are derived, where the carrier-impurity correlations are taken into account. In the Markov limit, rates for the electron-impurity spin transfer can be derived for electron spins parallel and perpendicular to the impurity spins corresponding to measurable decay rates in Kerr experiments in Faraday and Voigt geometry. Our rigorous microscopic quantum kinetic treatment automatically accounts for the fact that, in an individual spin flip-flop scattering process, a spin flip of an electron is necessarily accompanied by a flop of an impurity spin in the opposite direction and the corresponding change of the impurity Zeeman energy influences the final energy of the electron after the scattering event. This shift in the electron energies after a spin flip-flop scattering processes, which usually has been overlooked in the literature, turns out to be especially important in the case of extremely diluted magnetic semiconductors in an external magnetic field. As a specific example for a $\mathbf{k}$-dependent effective magnetic field the effects of a Rashba field on the dynamics of the carrier-impurity correlations in a Hg${}_{1-x-y}$Cd${}_y$Mn${}_x$Te quantum well are described. It is found that, although accounting for the Rashba interaction in the dynamics of the correlations leads to a modified $\mathbf{k}$-space dynamics, the time evolution of the total carrier spin is not significantly influenced. Furthermore, a connection between the present theory and the description of collective carrier-impurity precession modes is presented.

18 pages, 7 figures

References in corpus (12)

• Theory of ferromagnetic (III,Mn)V semiconductors
• Dilute ferromagnetic semiconductors: Physics and spintronic structures
• Femtosecond Coherent Control of Spin with Light in (Ga,Mn)As ferromagnets
• Electron spin relaxation in paramagnetic Ga(Mn)As quantum wells
• Ultrafast Probes of Nonequilibrium Hole Spin Relaxation in Ferromagnetic Semiconductor GaMnAs
• Spin dynamics in (III,Mn)V ferromagnetic semiconductors: the role of correlations
• Comparison between a quantum kinetic theory of spin transfer dynamics in Mn doped bulk semiconductors and its Markov limit for non-zero Mn magnetization
• Ultrafast spin dynamics in II-VI diluted magnetic semiconductors with spin-orbit interaction
• Non-Markovian Effects in the Spin Transfer Dynamics in Diluted Magnetic Semiconductors due to Excitation in Proximity to the Band Edge
• Effective Equations for the Precession Dynamics of Electron Spins and Electron-Impurity Correlations in Diluted Magnetic Semiconductors
• Non-perturbative Correlation Effects in Diluted Magnetic Semiconductors
• Relaxation and coherent oscillations in the spin dynamics of II-VI diluted magnetic quantum wells

Cited by in corpus (3)

• Influence of non-magnetic impurity scattering on the spin dynamics in diluted magnetic semiconductors
• Quantum kinetic equations for the ultrafast spin dynamics of excitons in diluted magnetic semiconductor quantum wells after optical excitation
• Nonexponential spin decay in a quantum kinetic description of the D'yakonov-Perel' mechanism mediated by impurity scattering