Crossover Behavior from Decoupled Criticality

Abstract

We study the thermodynamic phase transition of a spin Hamiltonian comprising two 3D magnetic sublattices. Each sublattice contains XY spins coupled by the usual bilinear exchange, while spins in different sublattices only interact via biquadratic exchange. This Hamiltonian is an effective model for XY magnets on certain frustrated lattices such as body centered tetragonal. By performing a cluster Monte Carlo simulation, we investigate the crossover from the 3D-XY fixed point (decoupled sublattices) and find a systematic flow toward a first-order transition without a separatrix or a new fixed point. This strongly suggests that the correct asymptotic behavior is a first-order transition.

10 pages, 3 figures; added references

References in corpus (9)

• Theory of Electron Nematic Order in LaOFeAs
• Ising and Spin orders in Iron-based Superconductors
• Dimensional reduction at a quantum critical point
• Electronic Orbital Currents and Polarization in Mott Insulators
• Multiple Magnon Modes and Consequences for the Bose-Einstein Condensed Phase in BaCuSi2O6
• Geometric Frustration and Dimensional Reduction at a Quantum Critical Point
• Emergent Symmetry and Dimensional Reduction at a Quantum Critical Point
• Quantum phase transitions and dimensional reduction in antiferromagnets with inter-layer frustration
• Fixed points in frustrated magnets revisited