Calendar of Physics Talks Vienna

Conference: From Electrons To Phase Transitions
Speaker:ORGANIZERS: Georg Kresse and Karsten Held (SFB ViCoM)
Abstract:SCOPE OF THE CONFERENCE: The description of phase transitions is among the most challenging tasks in solid state physics. From an electronic point of view, an accurate description of phase transitions requires highly accurate energy differences between competing phases, a goal that is not yet achievable using routine ab initio methods. The conference will give an overview of methods beyond DFT that show promise in this area. The description of the ionic degrees of freedom is equally compelling, often necessitating sophisticated sampling methods to accurately capture the entropic contributions and their changes along the transition pathway. The conference will highlight promising new developments in this area, as well as, technologically relevant applications. For further information and the individual talks please see: http://www.sfb-vicom.at/conference-2014-from-electrons-to-phase-transitions/
Date: Wed, 26.02.2014
Time: 09:00
Location:Christian Doppler Hörsaal, Boltzmanngasse 5, 1090 Vienna, University of Vienna

Transport properties of a 3D topological insulator based on a strained high mobility HgTe film
Speaker:Z. D. Kvon (Institute of Semiconductor Physics, Novosibirsk, Russia)
Abstract:The talk is devoted to transport properties of the three-dimensional topological insulator (3D TI) on the basis of a high mobility HgTe film with a top gate. Gate-controlled transitions between three states are observed: a 3D electron metal, 2D Dirac surface states and a 3D hole metal in the film. Typical resistivity versus gate voltage dependencies in zero magnetic field correspond to the Fermi energy near the top of the valence band and to a Dirac-like band. When the Fermi level is outside the gap a Landau scattering is detected between the 2D Dirac electrons and the bulk electrons/holes. An analysis of high- and low-field quantum oscillations highlights the interplay of the different carrier types and allows to probe the carrier density of top and bottom surfaces of the film in the TI regime separately.
Date: Wed, 26.02.2014
Time: 16:00
Duration: 45 min
Location:Seminarraum 138B, 7. OG Rot, Freihausgebäude, TU Wien, Wiedner Hauptstraße 8-10, 1040 Wien
Contact:Andrei Pimenov