Spin dynamics in magnetic topological insulators

• Grant number: 16/25639-2
• Support Opportunities: Research Grants - Visiting Researcher Grant - Brazil
• Start date: March 05, 2017
• End date: September 04, 2017
• Field of knowledge: Physical Sciences and Mathematics - Physics - Condensed Matter Physics
• Principal Investigator: Adalberto Fazzio
• Grantee: Adalberto Fazzio
• Visiting researcher: Antonio Tavares da Costa Junior
• Visiting researcher institution: Universidade Federal Fluminense (UFF). Instituto de Física, Brazil
• Host Institution: Centro de Engenharia, Modelagem e Ciências Sociais Aplicadas (CECS). Universidade Federal do ABC (UFABC). Ministério da Educação (Brasil). Santo André , SP, Brazil

Abstract

Topological insulators are materials whose electronic structure has bulk bandsidentical to those of a standard insulator but also has "metallic" (conducting) surface states. Propagation of electrons occupying those surface states isutterly insensitive to disorder; this property is known as "topological protection".The topological insulator's surface states are the main reason these materialshave been so intensively and extensively investigated recently. In principlethey could be used as "ideal" carriers for both charge and spin. The maingoal of this proposal is to elucidate the dynamical properties of magnetic topological insulators. To this end we will employ density functional theory methods for the determination of their electronic structure and many body theory methods to calculate their spin excitation spectra. We will investigate their spin and charge response to external electromagnetic fields. Our focus will be on the dynamics of magnetization and of the pure spin currents thatpropagate on the MTI surfaces. (AU)