Date(s) - 14/05/2015
12:00 pm - 1:00 pm
Title: Cyclotron motions in exotic semi-metals
Speaker: Jun-Won Rhim
Location: ABB 319
Recently, there has been a rising interest in novel
semi-metals such as the Weyl, nodal ring and quadratic band touching semi-metals. In many cases, those semi-metals not only exhibit unconventional physical properties but also have non-trivial topological natures. In this talk, I’m going to present unique characters of the cyclotron motions in the nodal ring and the quadratic band touching semi-metals. For the nodal ring case, in the first part of the talk, we show that the Dirac rings result in nearly flat zero modes in spite of its three dimensionality. Due to this property, the 3D quantum Hall effect is possible for certain set of band parameters. In the second part of the presentation, I will be talking about the unconventional aperiodic quantum oscillation behaviors in the quadratic band touching semi-metals. The similar aperiodicity was already observed in the Shubnikov de Haas experiment on Pr2Ir2O7 and we demonstrate that it originates from the inter-Landau level crossing and nonuniform Landau level spacings.