Edge spin accumulation in a two-dimensional electron gas with two subbands

• Grant number: 15/09190-2
• Support Opportunities: Research Grants - Visiting Researcher Grant - International
• Start date: July 19, 2015
• End date: August 30, 2015
• Field of knowledge: Physical Sciences and Mathematics - Physics - Condensed Matter Physics
• Principal Investigator: José Carlos Egues de Menezes
• Grantee: José Carlos Egues de Menezes
• Visiting researcher: Alexander Khaetskii
• Visiting researcher institution: State University of New York, Buffalo State (SUNY), United States
• Host Institution: Instituto de Física de São Carlos (IFSC). Universidade de São Paulo (USP). São Carlos , SP, Brazil

Abstract

The main goal of this research proposal is the quantitive description of recent experimental results published by Prof. Gusev's group at IFUSP, concerning the spin Hall effect (electrons) in two-subband quantum wells [Hernandez et al., Phys. Rev. B 88, 161305(R) (2013)]. These results are quite interesting because they (i) demonstrate for the first time the intrinsic spin Hall effect (as opposed to the extrinsic one due to impurities in the system) and (ii) corroborate an theoretical prediction by Prof. Egues' group at IFSC [Bernardes et al. Phys. Rev. Lett. 99, 076603 (2007)] for this type of intrinsic spin Hall effect in a two-subband quantum well. This theoretical prediction was based on a simple two-subband model in the ballistic regime. This is a surprising result since it is well known in the literature that a single-subband quantum well gives rise to a zero intrinsic spin Hall effect. Our project presents research plans to investigate in detail the experimental system (studied by the IFUSP group) thus obtaining a quantitative descriptions of their results and possibly gaining more insight and making further theoretical prediction of novel effects. (AU)