Volume 84, Number 3, November 2008
Article Number 37004
Number of page(s) 6
Section Condensed Matter: Electronic Structure, Electrical, Magnetic and Optical Properties
Published online 21 October 2008
EPL, 84 (2008) 37004
DOI: 10.1209/0295-5075/84/37004

Spin and charge shot noise in mesoscopic spin Hall systems

R. L. Dragomirova1, L. P. Zârbo1, 2 and B. K. Nikolić1

1  Department of Physics and Astronomy, University of Delaware - Newark, DE 19716-2570, USA
2  Department of Physics, Texas A&M University - College Station, TX 77843-4242, USA

received 30 June 2008; accepted in final form 22 September 2008; published November 2008
published online 21 October 2008

Injection of unpolarized charge current through the longitudinal leads of a four-terminal two-dimensional electron gas with the Rashba spin-orbit (SO) coupling and SO scattering off extrinsic impurities is responsible not only for the pure spin Hall current in the transverse leads, but also for non-equilibrium random time-dependent current fluctuations. We employ the scattering approach to current-current correlations in multiterminal nanoscale conductors to analyze the shot noise of transverse pure spin Hall current and zero charge current, or transverse spin current and non-zero charge Hall current, driven by unpolarized or spin-polarized injected longitudinal charge current, respectively. Since any spin-flip acts as an additional source of noise, we argue that these shot noises provide a unique experimental tool to differentiate between intrinsic and extrinsic SO mechanisms underlying the spin Hall effect in paramagnetic devices.

72.25.Dc - Spin polarized transport in semiconductors.
05.40.Ca - Noise.

© EPLA 2008