Java Hysteresis Simulation

version 0.9a, updated 24 May 1995

author: Paul Houle

Our applet simulates hysteresis using a random-field ising model developed by Jim Sethna and his group. You can run our model at three different values of the random field, which determines the influence of disorder on the system. With less disorder, such as R=0.5, you will observe very large avalanches as most of the system changes magnetization as once. R=1.0 is just about critical and you will observe both very small and very large avalanches. (R=1.0 is certainly critical for systems of dimension greater than 2, but we do not know for certain if there is a critical point in 2-d). R=2.0 is well above critical and you will see mostly small avalanches.

Run the simulation with
R=2.0, R=1.0, or R=0.5.

You can download the source code, browse the class documentation and source code for our applet, or find out more about the physics of hysteresis.

This applet is part of the NSF project Integration of Information Age Networking and Parallel Supercomputer Simulations into University General Science and K-12 Curricula.