Modulated Rashba interaction in a quantum wire: Spin and charge dynamics

Details Modulated Rashba interaction in a quantum wire: Spin and charge dynamics Modulated Rashba interaction in a quantum wire: Spin and charge dynamics

2011-05-18

arxiv.org/abs/1105.4141v2

Phys. Rev. B 84, 075466 (2011)

Physics

Condensed Matter

Strongly Correlated Electrons

20 pages, 6 figures

Scientific paper

10.1103/PhysRevB.84.075466

It was recently shown that a spatially modulated Rashba spin-orbit coupling in a quantum wire drives a transition from a metallic to an insulating state when the wave number of the modulation becomes commensurate with the Fermi wave length of the electrons in the wire. It was suggested that the effect may be put to practical use in a future spin transistor design. In the present article we revisit the problem and present a detailed analysis of the underlying physics. First, we explore how the build-up of charge density wave correlations in the quantum wire due to the periodic gate configuration that produces the Rashba modulation influences the transition to the insulating state. The interplay between the modulations of the charge density and that of the spin-orbit coupling turns out to be quite subtle: Depending on the relative phase between the two modulations, the joint action of the Rashba interaction and charge density wave correlations may either enhance or reduce the Rashba current blockade effect. Secondly, we inquire about the role of the Dresselhaus spin-orbit coupling that is generically present in a quantum wire embedded in semiconductor heterostructure. While the Dresselhaus coupling is found to work against the current blockade of the insulating state, the effect is small in most materials. Using an effective field theory approach, we also carry out an analysis of effects from electron- electron interactions, and show how the single-particle gap in the insulating state can be extracted from the more easily accessible collective charge and spin excitation thresholds. The smallness of the single-particle gap together with the anti-phase relation between the Rashba and chemical potential modulations pose serious difficulties for realizing a Rashba-controlled current switch in an InAs-based device. Some alternative designs are discussed.

Affiliated with

Also associated with

No associations

Rating

Modulated Rashba interaction in a quantum wire: Spin and charge dynamics 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 Modulated Rashba interaction in a quantum wire: Spin and charge dynamics, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Modulated Rashba interaction in a quantum wire: Spin and charge dynamics will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-70829