Antiferromagnetic Ising model applet: simulation in the multicanonical ensemble with the Wang-Landau algorithm
Applet help: The S(E) chart on the right side displays the estimate of the microcanonical entropy S(E) in real time. The south-panel displays charts of reweighted thermodymical averages as a funtion of temperature. The "F(kT,E)" button let you visualize the variational free energy. For second-order transitions (as is the case for the AF Ising model), and near the transition temperature, you should witness a single clear minimum. The "temperature" button let you configure many things regarding the simulation, e.g. temperature range for the reweighting procedure, number of measurements between checks histogram roughness, ... if the applet runs too slowly, reduce the "Latency". If still slow, deselect the "Animate" checkbox. Download source code : montecarlo.zip

S. Reynal (ENSEA/UCP)