correlation.m

Correlation order selection function - keeps only the specified orders of spin correlation in the state vector. This is useful as a replacement for gradients and phase cycles because correlation order filtering can be accomplished analytically, by just picking out the required correlation orders and zeroing everything else.

Syntax

    rho=correlation(spin_system,rho,correlation_orders,spins)

Parameters

  rho     -  a state vector or a horizontal stack thereof;
             in zeeman-hilb, a density matrix or a horizon-
             tal stack thereof

  correlation_orders  -  a row vector of correlation
                         orders to keep

  spins               -  which spins to consider (e.g.
                         '1H', '13C', 'all')

Outputs

  rho     - the state vector with the undesired orders of
            spin correlations zeroed out

Notes

This function requires sphten-liouv, zeeman-liouv, or zeeman-hilb formalism; Fokker-Planck direct products are supported in the Liouville space formalisms. In the Zeeman formalisms the selection is an exact projection built from per-spin identity component channels because correlation order is not diagonal in the Zeeman basis; zeeman-hilb density matrices are stretched into Liouville space, filtered there, and folded back.

See also

adelim.m, coherence.m, dfpt.m, homospoil.m, human2opspec.m, lin2lm.m, lin2lmn.m, lm2lin.m, lmn2lin.m, path_trace.m, scomponents.m, sinkhole.m, sparse2csr.m, sphten2zeeman.m, stitch.m, zte.m, Kernel_functions, Kernel_utilities

Version 2.8, authors: Ilya Kuprov, Luke Edwards