“Progress in the comparison of ARPES to DMFT for d and f strongly correlated electron systems”

 Dr. Jonathan Denlinger, Lawrence Berkeley National Lab

 Mar. 2nd (Thu), 4:00 p.m , #1323(E6-2. 1^st fl.)

The comparison of angle-resolved photoemission (ARPES) to dynamical mean field theory (DMFT) electronic structure calculations is reviewed for three correlated electron systems of V2O3, CeCoIn5 and SmB6. The electronic structure of metallic phase V2O3, key to understanding its various metal-insulator transitions with temperature, doping and pressure, is revealed by ARPES to have a d-orbital band filling that is inconsistent with a 2007 DMFT model of correlation-enhanced orbital polarization, but is thematically consistent with more recent DMFT calculations stressing full charge-self-consistency.

   The Kondo lattice system CeCoIn5 is shown to exhibit itinerant f-electron participation in the localized-like 3D Fermi surface topology consistent with the low energy scale description of DMFT calculations, and with a temperature-dependence that extends far above the transport coherence temperature of T*~45K. 

   Finally, the temperature-dependent evolution of the bulk 4f electronic structure of mixed-valent SmB6 revealed by ARPES and DMFT identifies an important role in f-p hybridization assistance to the metal-insulator transition (MIT) beyond the minimal two-band models of f-d hybridization.  The current status of the topological insulator scenario for the SmB6 in-gap surface states is also reviewed.

Contact: Yeong Kwan Kim (Tel. 2516, yeongkwan@kaist.ac.kr)