Monte Carlo Simulation of the Smeared Phase Transition in a 3-Dimensional Ising Model with Planar Defects
Department
Physics
Major
Physics and Mathematics
Research Advisor
Vojta, Thomas
Advisor's Department
Physics
Funding Source
National Science Foundation, UM Research Board, Research Corporation
Abstract
We investigate the effects of rare regions on the dynamics of Ising magnets with planar defects, i.e., disorder perfectly correlated in two dimensions. In these systems, the magnetic phase transition is smeared because static, long range order can develop on isolated rare regions. We perform large-scale Monte Carlo simulations for a three- dimensional Ising model with nearest neighbor interactions and planar defects. To increase the efficiency of the calculations, we have developed parallel simulation algorithms and implemented them on the Pegasus Cluster. We find that in the tail region of the smeared transition, the dynamics is extremely slow, even slower than in a conventional Griffiths phase. The spin autocorrelation function decays like a stretched exponential at intermediate times before approaching the exponentially small equilibrium value following a power law at late times.
Biography
Ryan is a senior attending the University of Missouri--Rolla majoring in Physics and Mathematics. He has been an active student researcher at UMR working under both Dr. Thomas Vojta and Dr. Michael Schulz and has done a National Science Foundation Research Experience for Undergraduates at both The Pennsylvania State University and the California Institute of Technology. He is currently the President of the Society of Physics Students and has also served as Vice-President and Treasurer. He is a member of Sigma Pi Sigma, the physics honor fraternity.
Research Category
Natural Sciences
Presentation Type
Poster Presentation
Document Type
Poster
Presentation Date
12 Apr 2006, 1:00 pm
Monte Carlo Simulation of the Smeared Phase Transition in a 3-Dimensional Ising Model with Planar Defects
We investigate the effects of rare regions on the dynamics of Ising magnets with planar defects, i.e., disorder perfectly correlated in two dimensions. In these systems, the magnetic phase transition is smeared because static, long range order can develop on isolated rare regions. We perform large-scale Monte Carlo simulations for a three- dimensional Ising model with nearest neighbor interactions and planar defects. To increase the efficiency of the calculations, we have developed parallel simulation algorithms and implemented them on the Pegasus Cluster. We find that in the tail region of the smeared transition, the dynamics is extremely slow, even slower than in a conventional Griffiths phase. The spin autocorrelation function decays like a stretched exponential at intermediate times before approaching the exponentially small equilibrium value following a power law at late times.
Comments
Joint project with Shellie Huether