Hai-Feng Mu, Qing-Rong Zheng, Biao Jin, Gang Su ^∗

College of Physical Sciences, Graduate School of the Chinese Academy of Sciences, P.O. Box 4588, Beijing 100049, China

Received 10 December 2004; accepted 15 December 2004

Available online 7 January 2005

Communicated by V.M. Agranovich

Abstract:

    Current-induced spin transfer torque through a marginal Fermi liquid (MFL) which is connected to two noncollinearly aligned ferromagnets via tunnel junctions is discussed in terms of the nonequilibrium Green function method. It is found that in the absence of the spin–flip scattering, the magnitude of the torque increases with the polarization and the coupling constant λ of the MFL, whose maximum increases with λ linearly, showing that the interactions between electrons tend to enhance the spin torque. When the spin–flip scattering is included, an additional spin torque is induced. It is found that the spin–flip scattering enhances the spin torque and gives rise to a nonlinear angular shift. 

2005 Elsevier B.V. All rights reserved.

PACS: 75.47.-m; 74.20.Mn; 75.70.Cn