Year: 2012
Type: article
Abstract: We consider the effects of random fluctuations in the local geometry on the ground-state properties of a two-dimensional quantum antiferromagnet. We analyze the behavior of spins described by the Heisenberg model as a function of what we call phason disorder, following a terminology used for aperiodic systems. The calculations were carried out both within linear spin-wave theory and using quantum Monte Carlo simulations. An ``order by disorder'' phenomenon is observed in this model, wherein antiferromagnetism is found to be enhanced by phason disorder. The value of the staggered order parameter increases with the number of defects, accompanied by an increase in the ground-state energy of the system.
Source: Physical Review B
Institutions: Université Paris-Sud, Centre National de la Recherche Scientifique, Laboratoire de physique des Solides, Laboratoire de Physique Théorique et Hautes Energies, Université Pierre-et-Marie-Curie, HUN-REN Wigner Research Centre for Physics, Hungarian Academy of Sciences, RWTH Aachen University
Language: English
Subfield: Condensed Matter Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2078012794