TDGL: Time dependent Ginzburg-Landau solver

Fortran program, uses finite difference method based on gauge-invariant link variables. Reference: "On the numerical solution of the time-dependent Ginzburg-Landau equations in multiply connected domains", G. Buscaglia, C. Bolech and A. López, to appear in Connectivity&Superconductivity, J. Berger and J. Rubinstein (Eds.), Springer.

Here you can download

It should compile without trouble. The data file corresponds to a small case (case III in the reference), with 64x64 cells and 250,000 time steps. This case takes about thirty minutes to run on my PC (750 MHz). You will get two output files, c.dat and s.dat, of summary results. Most detailed is s.dat, of which the first column is the time-step number, the second the applied field, the third the internal field (inside the hole), the fourth the total average field (B), the fifth the magnetization, the sixth the free energy, the following two the number of fluxoids inside different paths and the last two the minimum values of the modulus of the order parameter along the same paths. By reading the program and the associated paper the meaning of these results should be evident. You will also get several graphic files (*.gra) containing the values of the modulus of the order parameter for each cell in the mesh, that you should be able to visualize with an appropriate package, and finally several restart files (*.ree). In case you wanted to reccommence a calculation from one of these restart files, all you must do is rename it as "tdgl.ree".

I'm sorry for the names of the graphics and restart files, I'm sure it can be done much better.

Anyway, just for testing, once you have run the code, if you plot the fifth column of s.dat as a function of the second column, you should find a nice magnetization curve as the following:
 
 

magnetization curve
 

Best wishes,

Gustavo C. Buscaglia, 20 July 2000