Parallel density matrix propagation in spin dynamics simulations

J Chem Phys. 2012 Jan 28;136(4):044108. doi: 10.1063/1.3679656.


Several methods for density matrix propagation in parallel computing environments are proposed and evaluated. It is demonstrated that the large communication overhead associated with each propagation step (two-sided multiplication of the density matrix by an exponential propagator and its conjugate) may be avoided and the simulation recast in a form that requires virtually no inter-thread communication. Good scaling is demonstrated on a 128-core (16 nodes, 8 cores each) cluster.