Hai-Feng Mu, Gang Su,* Qing-Rong Zheng, and Biao Jin

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

(Received 17 June 2004; revised manuscript received 25 August 2004; published 23 February 2005)

Abstract:

    Spin-polarized transport through a marginal Fermi liquid sMFLd which is connected to two noncollinear ferromagnets via tunnel junctions is discussed in terms of the nonequilibrium Green function approach. It is found that the current-voltage characteristics deviate obviously from the ohmic behavior, and the tunnel current increases slightly with temperature, in contrast to those of the system with a Fermi liquid. The tunnel magnetoresistance sTMRd is observed to decay exponentially with increasing bias voltage, and to decrease slowly with increasing temperature. With increasing coupling constant of the MFL, the current is shown to increase linearly, while the TMR is found to decay slowly. The spin-valve effect is observed.

DOI: 10.1103/PhysRevB.71.064412          PACS numberssd: 75.25.1z, 71.10.Ay, 73.40.Gk