Emergent critical phase and Ricci flow in a 2D frustrated Heisenberg model

ORAL

Abstract

We introduce a two-dimensional frustrated Heisenberg antiferromagnet on interpenetrating honeycomb and triangular lattices [1]. Classically the two sublattices decouple, and ``order from disorder'' drives them into a coplanar state. Applying Friedan's geometric approach to nonlinear sigma models, we obtain the scaling of the spin-stiffnesses governed by the Ricci flow of a 4D metric tensor. At low temperatures, the relative phase between the spins on the two sublattices is described by a six-state clock model with an emergent critical phase and two Berezinskii-Kosterlitz-Thouless (BKT) phase transitions.\\[4pt] [1] Peter P. Orth, Premala Chandra, Piers Coleman, and J\"org Schmalian, arXiv:1206.5740v1 (2012) (accepted for Phys. Rev. Lett.)

Authors

  • Peter P. Orth

    Karlsruhe Institute of Technology (KIT), Germany, Karlsruhe Institute of Technology (KIT)

  • Premala Chandra

    Rutgers University

  • Piers Coleman

    Rutgers University, Center for Materials Theory Department of Physics \& Astronomy, Rutgers University, Center for Materials Theory, Rutgers University, Piscataway, NJ 08854, USA, Center for Materials Theory, Physics and Astronomy, Rutgers University

  • Joerg Schmalian

    Karlsruhe Institute of Technology, Institut f\"ur Theorie der Kondensierten Materie and DFG Center for Functional Nanostructures, Karlsruher Institut f\"ur Technologie, Germany, Karlsruhe Institute of Technology (KIT)