Correlated Dirac liquids in three dimensions

Datum

28.07.2015

Zeit

14:00 - 15:00

Sprecher

Bitan Roy

Zugehörigkeit

University of Maryland

Sprache

en

Hauptthema

Physik

Andere Themen

Physik

Host

CMT seminars

Beschreibung

Three-dimensional Dirac semimetals can be realized at the quantum critical point between topological and trivial insulators, and also as a stable phase of matter. In this talk, I will discuss the effects of electron-electron interactions in these systems. I will demonstrate that when interactions are sufficiently weak topological to trivial insulator transition continues to be a continuous one. On the other hand, when interaction is strong enough such transition becomes first order in nature. Experimental ramifications of such outcomes will be discussed. During the second half of this talk, I will discuss the effect of quantizing magnetic fields in Dirac semimetals. I will show that in strong magnetic fields, the conical dispersion in this system quenches onto a set of highly degenerate Landau levels. In particular, the topologically protected zeroth landau level is composed of one-dimensional dispersive modes. Consequently, weak enough repulsive interaction is sufficient to cause hybridization among them and support a charge-density-wave order that can be axionic in nature. Scaling of such interaction induced gap in magnetic field and its signature on various measurable quantities will be discussed.

Letztmalig verändert: 28.07.2015, 09:46:00