2008/05/31 by Jian‐Hua Jiang, J. H. Jiang, M. W. Wu +2
Physics and Astronomy · #Biology #Coherence (philosophical gambling strategy) #Electron #Physics #Quantum #Quantum and electron transport phenomena #Quantum mechanics #Quantum optics and atomic interactions #Semiconductor Quantum Structures and Devices #Spin (aerodynamics) #Thermodynamics #Type (biology) #cond-mat.mtrl-sci
paper · pdf · doi:10.1103/physrevb.78.125309
published as Phys. Rev. B 78, 125309 (2008). · 17 pages, 16 figures, Phys. Rev. B 78, 2008, in press
arxiv created 2008/08/20 · openalex publication_date 2008/09/08 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Spin kinetics in n-type InAs quantum wells under intense terahertz laser fields is investigated by developing fully microscopic kinetic spin Bloch equations via the Floquet-Markov theory and the nonequilibrium Green's function approach, with all the relevant scattering, such as the electron-impurity, electron-phonon, and electron-electron Coulomb scattering explicitly included. We find that a finite steady-state terahertz spin polarization induced by the terahertz laser field, first predicted by Cheng and Wu [Appl. Phys. Lett. 86, 032107 (2005)] in the absence of dissipation, exists even in the presence of all the scattering. We further discuss the effects of the terahertz laser fields on the spin relaxation and the steady-state spin polarization. It is found that the terahertz laser fields can strongly affect the spin relaxation via hot-electron effect and the terahertz-field-induced effective magnetic field in the presence of spin-orbit coupling. The two effects compete with each other, giving rise to nonmonotonic dependence of the spin-relaxation time as well as the amplitude of the steady-state spin polarization on the terahertz field strength and frequency. The terahertz field dependences of these quantities are investigated for various impurity densities, lattice temperatures, and strengths of the spin-orbit coupling. Finally, the importance of the electron-electron Coulomb scattering on spin kinetics is also addressed.