Parts | Days | Selection | Search | Updates | Downloads | Help

TT: Fachverband Tiefe Temperaturen

TT 55: TR: Topological Insulators 1 (jointly with HL and MA)

TT 55.4: Talk

Thursday, March 17, 2011, 16:45–17:00, HSZ 304

Multidimensional Angle-Resolved Photoemission Spectroscopy: Application to Topological Insulators — •Ovsyannikov R.¹, Lupulescu C.^1,2, Rienks E.D.L.¹, Fink J.¹, King P.D.C.³, Baumberger F.³, Hatch R.C.⁴, Hofmann P.⁴, Mi J.⁴, Iversen B.B.⁴, Lindblad A.⁵, Svensson S.^5,6, and Eberhardt W.^1,2 — ¹Helmholtz Zentrum Berlin, Berlin, Germany — ²Technische Universität Berlin, Berlin, Germany — ³University of St Andrews, St Andrews, UK — ⁴Aarhus University, Aarhus, Denmark — ⁵MAX-lab, Lund, Sweden — ⁶Uppsala University, Uppsala, Sweden

We will present a novel approach of performing photoelectron spectroscopy experiments and demonstrate its potential on the prototype topological insulator Bi₂Se₃. We use VG Scienta’s ARTOF 10k, a time-of-flight electron spectrometer which combines position-sensitive detection with an advanced focusing electron lens system. The instrument allows the simultaneous recording of kinetic energy and the angular pattern of photoelectrons in a cone of up to 30^∘ opening angle with very high resolution. Additionally, the temporal evolution of the sample electronic structure can be easily extracted from the corresponding data set. The experiments were carried out at the 10m NIM beamline at the BESSY II synchrotron facility, when operating in single bunch mode. We will show the temporal evolution of the topological state and the subsequent formation of a two-dimensional electron gas at the (0001) surface of the topological insulator Bi₂Se₃. We will also discuss the overall time resolution of the experimental setup.