ngce.m

Numerical integral route to the Redfield relaxation superoperator.

Syntax

R=ngce(spin_system,H0,H1,dt,tau_est,reg)

Arguments

H0 - static laboratory frame Hamiltonian commutation su-

      peroperator acting in the background, a matrix

 H1 - stochastic part (zero mean) of the laboratory frame
      Hamiltonian commutation superoperator, a cell array
      of matrices for each point in the MD trajectory.

 dt - time step of the MD trajectory, seconds

 tau_est - correlation tiume estimate for internal safety
           control, seconds

 reg - optional overall relaxation rate, this is added to 
       every eigenvalue of the resulting matrix to prevent
       very small relaxation rates (e.g. singlets) from 
       jumping into positive due to integration accuracy
       limits and then causing problems

Outputs

R - laboratory frame relaxation superoperator

Note: enough trajectory points must be present to converge
      the ensemble averages and Redfield's integral.

Note: the result is returned in the LABORATORY FRAME - eli-
      minating non-secular terms is user's responsibility.

ilya.kuprov@weizmann.ac.il
jpresteg@uga.edu

Examples

See our recent paper with Jim Prestegard: https://doi.org/10.1016/j.jmr.2020.106891

Notes

Enough trajectory points must be present to converge the ensemble averages and Redfield's integral.

See also

relaxation.m, lindbladian.m, magpump.m

Version 2.6, authors: Ilya Kuprov, Jim Prestegard