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

TT: Fachverband Tiefe Temperaturen

TT 18: f-Electron Systems and Heavy Fermions II

TT 18.2: Talk

Monday, March 12, 2018, 15:15–15:30, H 3005

Kondo insulators vs. transition metal-based narrow-gap semiconductors — •Jan M. Tomczak — Institute of Solid State Physics, TU Wien, Austria

Kondo insulators display a pronounced temperature dependence in their experimental observables: An insulating low-temperature regime with an activated magnetic susceptibility gives way—above a coherence temperature—to metallic conduction and Curie-Weiss behaviour. Empirically, this crossover is strikingly akin to that found in some correlated narrow-gap semiconductors, such as FeSi and FeSb₂, which are based on transition metals. Here, we present realistic many-body calculations for the prototypical Kondo insulator Ce₃Bi₄Pt₃[1] and compare them to our previous results for FeSi[2]. We discuss simulated transport properties, as well as photoemission and optical spectra. Further, we propose a microscopic distinction between the physics of both compounds from the perspective of dynamical mean-field theory. This work was supported by the Austrian Science Fund (FWF) through project P 30213-N36.
JMT, Topical Review for J. Phys.: Condens. Matter (submitted),
JMT, K. Haule, G. Kotliar, PNAS 109, 3243 (2012)