Quantum Dot as a Spin--Current Diode

Details Quantum Dot as a Spin--Current Diode Quantum Dot as a Spin--Current Diode

2006-11-13

arxiv.org/abs/cond-mat/0611336v2

Phys. Rev. B 75, 165303 (2007)

Physics

Condensed Matter

Mesoscale and Nanoscale Physics

7 two-column pages, 5 figures. v2 (published): title changed, some added text to Sec. II and Appendix and some minor changes t

Scientific paper

10.1103/PhysRevB.75.165303

We report a study of spin dependent transport in a system composed of a quantum dot coupled to a normal metal lead and a ferromagnetic lead (NM-QD-FM). We use the master equation approach to calculate the spin-resolved currents in the presence of an external bias and an intra-dot Coulomb interaction. We find that for a range of positive external biases (current flow from the normal metal to the ferromagnet) the current polarization $\wp=(I_\uparrow-I_\downarrow)/(I_\uparrow+I_\downarrow)$ is suppressed to zero, while for the corresponding negative biases (current flow from the ferromagnet to the normal metal) $\wp$ attains a relative maximum value. The system thus operates as a rectifier for spin--current polarization. This effect follows from an interplay between Coulomb interaction and nonequilibrium spin accumulation in the dot. In the parameter range considered, we also show that the above results can be obtained via nonequilibrium Green functions within a Hartree-Fock type approximation.

Affiliated with

Also associated with

No associations

Rating

Quantum Dot as a Spin--Current Diode does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Quantum Dot as a Spin--Current Diode, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Quantum Dot as a Spin--Current Diode will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-669167