Bose-Einstein condensation of Dirac magnons

ORAL

Abstract

The discovery of graphene, a two dimensional material which hosts massless linearly dispersive quasiparticles, has led to an extensive research in Dirac fermions in the last decade. The effect of interaction in the stability and renormalization of Dirac cone attracted considerable attention. With the expanding list of fermionic Dirac materials, the idea of bosonic Dirac materials has emerged. In our previous works, we have established the notion of Dirac bosons. In this paper, we analyze and predict the condition for the formation of Bose-Einstein condensation (BEC) by Dirac magnons in Chromium tri-halides CrX3 (X= Fl, Br and I). The BEC order parameter has a spinor structure and modulates with finite momentum at the Dirac point. We also discuss the dynamics of the two component/spinorial BEC order parameter by a Dirac Gross-Pitaevskii equation. Our work is motivated by a recent experimental observation (PRL 112, 116402 (2014)) of polaritonic Bose-Einstein condensation in honeycomb lattice.

*US DOE BES E3B7, LDRD XWFL, Knut and Alice Wallenberg foundation (Grant No. KAW-2013.0020) and ERC DM 321031.

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Presenters

  • Saikat Banerjee

    • NORDITA
    • Nordita

Authors

  • Saikat Banerjee

    • NORDITA
    • Nordita

  • Alexander Balatsky

    • NORDITA
    • Institute for Materials Science, Los Alamos National Laboratory
    • Nordita
    • Los Alamos Natl Lab
    • Nordita, KTH Royal Institute of Technology and Stockholm University; Institute for Materials Science, Los Alamos National Laboratory; Department of Physics, University of Conn
    • Instittute for Materials Science, Los Alamos National Laboratory
    • Institute for Materials Science, Los Alamos National Laboratory/Nordita/University of Connecticut