Computer Simulations of Phase Transitions

University Of Georgia Research Foundation Inc, Athens GA

Investigators

Abstract

This award supports research that will utilize methods of computer simulation to complement traditional theoretical and experimental approaches to the study of diverse, important problems in statistical physics. The basic techniques to be used include Monte Carlo and spin dynamics simulations, the actual implementations of which are already quite sophisticated. A broad range of models will be examined, including those with relevance to magnetic materials, binary semiconductor alloys, growing films, and disordered media. In this latter class of systems are models with intrinsic local frustration, e.g., magnetic spins on a pyrochlore lattice. Both static and dynamic critical phenomena for systems in equilibrium will be carefully examined, and simple non-equilibrium models related to film growth and superionic diffusion (driven diffusive systems) will be studied as well. Several of the systems will allow particles to move continuously in space, subject to elastic interactions, whereas others will be confined to rigid lattices (including classical spins with continuous degrees of freedom) with discrete near neighbor interactions. In some cases, finite geometries and/or the presence of walls will be responsible for behavior which is fundamentally different from that which is found in the bulk. The over-arching objective of the research will be to discover new phenomena and to provide a fundamental understanding of the behavior of all of the systems studied. Part of this effort will also focus on the development and refinement of new simulation methods that will further enhance our ability to study phase transitions in systems that cannot be treated analytically. Whenever possible, results will be compared with those from theory and/or experiment. The combination of the discovery and explanation of physical phenomena together with the anticipated methodological developments forms a coherent activity with substantial intellectual merit. Broader impacts of this research will result from the applications of the models studied to other fields, as well as the development of methods that can also be widely applied. In addition, students at all levels will benefit. Some funds will be used to support student participation in an annual workshop on simulational physics. %%% This award supports research that will utilize methods of computer simulation to complement traditional theoretical and experimental approaches to the study of diverse, important problems in statistical physics. The basic techniques to be used include Monte Carlo and spin dynamics simulations, the actual implementations of which are already quite sophisticated. A broad range of models will be examined, including those with relevance to magnetic materials, binary semiconductor alloys, growing films, and disordered media. Broader impacts of this research will result from the applications of the models studied to other fields, as well as the development of methods that can also be widely applied. In addition, students at all levels will benefit. Some funds will be used to support student participation in an annual workshop on simulational physics. ***