Transport in topological insulator and semiconductor nanostructures

• Grant number: 11/20221-6
• Support type: Regular Research Grants
• Duration: March 01, 2012 - May 31, 2014
• Field of knowledge: Physical Sciences and Mathematics - Physics - Condensed Matter Physics
• Principal researcher: Gennady Gusev
• Grantee: Gennady Gusev
• Home Institution: Instituto de Física (IF). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

The recent discovery of topological insulators as well as other advances in basic condensed matter physics, enables new applications that exploit this new knowledge. The insulating properties of these surfaces may result in new spintronic or magnetic devices. Moreover, in combination with superconductors, topological insulators can lead to a new computer architecture that have quantum bit with topological properties. These insulators have had a considerable impact on the physics of condensed matter, making clear that topological effects which are intended only for low temperatures and high magnetic fields and can determine the materials physics of macroscopic systems under ambient conditions.We propose the study of states of topological insulators and quantum spin Hall effect (quantum spin-Hall effect QSHE) in semiconductor structures of HgTe / CdTe produced at the Institute of Physics of Semiconductors, the Novosibirsk. This system is characterized by the effects of the Rashba spin orbit stronger (getting tens meV, respectively, and is comparable with the Fermi energy).The study of topological insulators and quantum spin Hall effect in semiconductor structures of HgTe / CdTe and collaborations between IFUSP and Institute of Semiconductor Physics began in 2007 with proposals to FAPESP (aid to visiting researchers: 2007/07953-2, 2008 / 09212-2, 2010/10097-3). Several studies have been published and submitted (among them a PRL) involving the use of these samples [Ref.1-3], and several works are in preparation.Some benefits of this project are: the evolution of knowledge of the physics of nanostructured systems, the development of techniques for characterization of HgTe quantum wells of high quality and the possible application of this knowledge (or its consequences) in future spintronic devices. (AU)