Thermodynamic properties of the two-dimensional S=1/2 Heisenberg antiferromagnet coupled to bond phonons

Abstract

By applying a quantum Monte Carlo procedure based on the loop algorithm we investigate thermodynamic properties of the two-dimensional antiferromagnetic S=1/2 Heisenberg model coupled to Einstein phonons on the bonds. The temperature dependence of the magnetic susceptibility, mean phonon occupation numbers and the specific heat are discussed in detail. We study the spin correlation function both in the regime of weak and strong spin phonon coupling (coupling constants g=0.1, w=8J and g=2, w=2J, respectively). A finite size scaling analysis of the correlation length indicates that in both cases long range Neel order is established in the ground state.

10 pages, 13 figures

References in corpus (5)

• Effective Spin Models for Spin-Phonon Chains by Flow Equations
• Spin-Phonon Chains with Bond Coupling
• Ground-state properties of two-dimensional dimerized Heisenberg models
• Quantum mechanics on Riemannian Manifold in Schwinger's Quantization Approach I
• Spin-Peierls Dimerization of a s=1/2 Heisenberg Antiferromagnet on a Square Lattice

Cited by in corpus (4)

• Valence-Bond Order in a Honeycomb Antiferromagnet Coupled to Quantum Phonons
• Structural and magnetic instabilities of layered magnetic systems
• Thermodynamics of a Spin-1/2 Chain Coupled to Einstein Phonons
• Neel to spin-Peierls transition in a quasi-1D Heisenberg model coupled to bond phonons