Europhys. Lett.
Volume 75, Number 2, July 2006
Page(s) 281 - 286
Section Condensed matter: electronic structure, electrical, magnetic, and optical properties
Published online 23 June 2006
Europhys. Lett., 75 (2), pp. 281-286 (2006)
DOI: 10.1209/epl/i2006-10113-x

Spin current in a two-dimensional electron gas tunnelling junction

J. Wang and K. S. Chan

Department of Physics and Materials Science, City University of Hong Kong Tat Chee Avenue, Kowloon, Hong Kong, PRC

received 6 January 2006; accepted in final form 31 May 2006
published online 23 June 2006

We report a novel phenomenon of dissipationless spin current in nonmagnetic tunnelling junctions, composed of two high mobility two-dimensional electron gases (2DEG) with either Rashba or Dresselhaus spin-orbital interaction as well as an insulator barrier between them. We find that, at zero bias, an equilibrium spin current flows in the junction without any charge current. The physical origin is the exchange coupling between two pseudomagnetic fields in 2DEG leads and it is similar to the super current in a Josephson junction.

73.23.-b - Electronic transport in mesoscopic systems.
72.25.Dc - Spin polarized transport in semiconductors.
71.70.Ej - Spin-orbit coupling, Zeeman and Stark splitting, Jahn-Teller effect.

© EDP Sciences 2006