Universal Rashba spin precession of two-dimensional electrons and holesM. G. Pala1, 2, M. Governale2, J. König2 and U. Zülicke2
1 Dipartimento di Ingegneria dell'Informazione - via Diotisalvi 2, I-56126 Pisa, Italy
2 Institut für Theoretische Festkörperphysik, Universität Karlsruhe D-76128 Karlsruhe, Germany
(Received 10 June 2003; accepted in final form 5 January 2004)
We study spin precession due to Rashba spin splitting of electrons and holes in semiconductor quantum wells. Based on a simple analytical expression that we derive for the current modulation in a broad class of experimental situations of ferromagnet/nonmagnetic semiconductor/ferromagnet hybrid structures, we conclude that the Datta-Das spin transistor i) is feasible with holes and ii) its functionality is not affected by integration over injection angles. The current modulation shows a universal oscillation period, irrespective of the different forms of the Rashba Hamiltonian for electrons and holes. The analytic formulas approximate extremely well exact numerical calculations of a more elaborate Kohn-Luttinger model.
85.75.Hh - Spin polarized field effect transistors.
72.25.-b - Spin polarized transport.
73.23.Ad - Ballistic transport.
© EDP Sciences 2004