Codes for running hierarichal equation of motion. This code is for a simple spin-Boson problem, however the code itself is general. Reproduces figure 5 of Strumpfer Schulten, JCTC 8, 2808 (2012). Help also taken from Chen, Zheng, Shi, Tan, JCP 131, 094502 (2009)
The details of the parameters are in the file spectra_heom.inp and in the subroutine setup_parameters in the file mod_spectra_heom.f90.
To run, type make (uses gfortran). Run with ./aout. Should take a few seconds. Creates a file rho.out that has the diagonal entries of the density matrix as a function of time.
The code can also be run with parallelization using openmp. For this, type 'make openmp'. The number of threads is set to 4 currently. The number of threads can be easily changed by editing the makefile statement 'export OMP_NUM_THREADS=4' Here change 4 to the desired number of threads.
Let me know if you need any questions.