Nematicity with a twist: Rotational symmetry breaking in a moiré superlattice
Rafael M. Fernandes, Jörn W. F. Venderbos
Abstract
symmetry, the system can still undergo a nematic-flop phase transition that spontaneously breaks in-plane twofold rotations. Moreover, elastic fluctuations, manifested as acoustic phonons, mediate a nemato-orbital coupling that ties the nematic director orientation to certain soft directions in momentum space, rendering the Potts-nematic transition mean field and first order. In contrast to the case of rigid crystals, the Fermi surface hot spots associated with these soft directions are maximally coupled to low-energy nematic fluctuations in the moiré superlattice case.
Topics & Concepts
SuperlatticeTwistMoiré patternCondensed matter physicsPhysicsSymmetry breakingLiquid crystalQuantumRotational symmetryQuantum mechanicsOpticsGeometryMechanicsMathematicsPhysics of Superconductivity and MagnetismCold Atom Physics and Bose-Einstein CondensatesTopological Materials and Phenomena