Parts | Days | Selection | Search | Updates | Downloads | Help
HL: Fachverband Halbleiterphysik
HL 4: Spintronics: Nanostructures and Optics
HL 4.8: Talk
Monday, March 7, 2016, 11:45–12:00, H13
Elliott-Yafet spin relaxation revisited — •Svenja Vollmar1, 2 and Hans Christian Schneider1 — 1Department of Physics and Research Center of OPTIMAS, University of Kaiserslautern — 2Graduate School of Excellence Materials Science in Mainz
By computing the dynamics of the reduced electronic density matrix, we present a new analysis of the Elliott-Yafet spin relaxation mechanism, i.e. the spin relaxation due to incoherent electron-phonon scattering [1,2,3]. In our approach spin dynamics is described correctly without approximating mixed spin states by pure spin states, as done in Yafet’s original treatment [3]. Our approach is therefore also valid for pronounced spin mixing. The central new quantity introduced in our calculation is a torque matrix element that determines the spin dynamics in a transparent fashion.
For the special case of Kramers degenerate bands we use this result to derive a novel expression for the close-to-equilibrium spin relaxation-time. To this end, we determine the reduced density matrix for a spin polarized system with arbitrary spin mixing in quasi-equilibrium [4].
[1] A. W. Overhauser, Phys. Rev. 89, 689 (1953).
[2] R. J. Elliott, Phys. Rev. 96, 266 (1954).
[3] Y. Yafet, Solid State Physics 14, 1 (1963).
[4] A. Baral, S. Vollmar, S. Kaltenborn, H.C. Schneider, arXiv: 1505.01432.