Dartmouth Events

Abstract: The dynamics of plasmons and sound modes in 2D Dirac materials have been studied extensively close to the Dirac point, for example 2D graphene. In the limit of decreasing doping of the 2D graphene sheet the Fermi temperature, TF, tends to zero and it is possible to reach the classical limit where TF/T << 1. In this temperature range this system should display classical hydrodynamic behavior of the collective modes. There has been a considerable amount of work on collective modes in 2D Dirac materials in the classical regime but there has not been as much interest in the quantum liquid limit where, T/TF<< 1. In this talk I will focus on 3D Dirac materials in the quantum liquid (Fermi/Dirac liquid) regime. In 3D the Landau Fermi Liquid Theory (LFLT) is a highly developed phenomenology and it provides detailed calculations and experimental confirmations of its validity. One of the reasons we have developed the LFLT for 3D Dirac liquids is to see where it differs from the traditional 3D LFLT of the properties like the collective modes, the density modes (zero and first sound ), the plasmon, and spin waves, to name a few. Another reason for studying the 3D Dirac materials is the ability to tune TF over a reasonable range of doping. An example would be the 3D Dirac semi-metal, Na3Bi, where we will study the properties of the 3D Dirac liquid in the quantum liquid regime as a function of temperature and density.

 

Hosted by Joshuah Heath