Thermodynamics of a gas of deconfined bosonic spinons in two dimensions

Abstract

We consider the quantum phase transition between a Neel antiferromagnet and a valence-bond solid (VBS) in a two-dimensional system of S=1/2 spins. Assuming that the excitations of the critical ground state are linearly dispersing deconfined spinons obeying Bose statistics, we derive expressions for the specific heat and the magnetic susceptibility at low temperature T. Comparing with quantum Monte Carlo results for the J-Q model, which is a candidate for a deconfined Neel-VBS transition, we find excellent agreement, including a previously noted logarithmic correction in the susceptibility. In our treatment, this is a direct consequence of a confinement length scale Lambda which is proportional to the correlation length xi raised to a non-trivial power; Lambda ~ xi^(1+a) ~1/T^(1+a), with a>0 (with a approximately 0.2 in the model).

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References in corpus (7)

• "Deconfined" quantum critical points
• Evidence for deconfined quantum criticality in a two-dimensional Heisenberg model with four-spin interactions
• 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
• Quantum criticality of U(1) gauge theories with fermionic and bosonic matter in two spatial dimensions
• Comprehensive quantum Monte Carlo study of the quantum critical points in planar dimerized/quadrumerized Heisenberg models
• Quantum critical scaling behavior of deconfined spinons

Cited by in corpus (8)

• Bridging lattice-scale physics and continuum field theory with quantum Monte Carlo simulations
• Correlated valence-bond states
• Dual dynamic scaling in deconfined quantum criticality
• Violation of the Spin Statistics Theorem and the Bose-Einstein Condensation of Particles with Half Integer Spin
• Thermodynamic and Dynamical Signatures of a Quantum Spin-Hall Insulator to Superconductor Transition
• Quantum criticality at finite temperature for two-dimensional $J{Q}_3$ models on the square and the honeycomb lattices
• Ground state energy density, susceptibility, and Wilson ratio of a two-dimensional disordered quantum spin system
• Z${}_2$ topological orders in kagomé dipolar systems: Feedback from Rydberg quantum simulator