Thermal valence-bond-solid transition of quantum spins in two dimensions

Abstract

We study the S=1/2 Heisenberg (J) model on the two-dimensional square lattice in the presence of additional higher-order spin interactions (Q) which lead to a valence-bond-solid (VBS) ground state. Using quantum Monte Carlo simulations, we analyze the thermal VBS transition. We find continuously varying exponents, with the correlation-length exponent "nu" close to the Ising value for large Q/J and diverging when Q/J approaches the quantum-critical point (the critical temperature Tc -> 0). This is in accord with the theory of deconfined quantum-critical points, which predicts that the transition should approach a Kosterlitz-Thouless (KT) fixed point when Tc -> 0+ (while the transition versus Q/J for T=0 is in a different class). We find explicit evidence for KT physics by studying the emergence of U(1) symmetry of the order parameter at T=T_c when Tc -> 0.

5 pages, 5 figures

References in corpus (13)

• "Deconfined" quantum critical points
• Quantum criticality beyond the Landau-Ginzburg-Wilson paradigm
• Evidence for deconfined quantum criticality in a two-dimensional Heisenberg model with four-spin interactions
• Quantum magnetism and criticality
• Scaling in the Fan of an Unconventional Quantum Critical Point
• From an Antiferromagnet to a Valence Bond Solid: Evidence for a First Order Phase Transition
• Bridging lattice-scale physics and continuum field theory with quantum Monte Carlo simulations
• Deconfined criticality flow in the Heisenberg model with ring-exchange interactions
• Location of the Potts-critical end point in the frustrated Ising model on the square lattice
• Quantum phase transitions in bilayer SU(N) anti-ferromagnets
• Large-N estimates of universal amplitudes of the CP^{N-1} theory and comparison with the JQ model
• Thermodynamics of a gas of deconfined bosonic spinons in two dimensions
• Quantum Phase Transition in the Four-Spin Exchange Antiferromagnet

Cited by in corpus (13)

• Transitions to valence-bond solid order in a honeycomb lattice antiferromagnet
• Columnar order and Ashkin-Teller criticality in mixtures of hard-squares and dimers
• Valence-bond solids, vestigial order, and emergent SO(5) symmetry in a two-dimensional quantum magnet
• Field-driven quantum phase transitions in $S=1/2$ spin chains
• Estimating the Critical Parameters of the Hard Square Lattice Gas Model
• Thermal Phase Transition of Generalized Heisenberg Models for SU(N) Spins on Square and Honeycomb Lattices
• Metamagnetism and zero-scale-factor universality in the two-dimensional $J$-$Q$ model
• 1D valence bond solids in a magnetic field
• Resummation-based Quantum Monte Carlo for Entanglement Entropy Computation
• Bose-Einstein condensation of deconfined spinons in two dimensions
• Thermodynamic and Dynamical Signatures of a Quantum Spin-Hall Insulator to Superconductor Transition
• Phase diagram of a square lattice model of XY Spins with direction-dependent interactions
• Phase diagram and Ashkin-Teller universality in the classical square-lattice Heisenberg-compass model