Sided product superoperator in the spherical tensor basis set. Returns superoperators corresponding to right or left multiplication of a density matrix by a user-specified operator. Syntax:
opspec - Spinach operator specification described in Sections 2.1 and 3.3 of the following paper:
side - 'left' or 'right' causes the function to return a product superoperator corresponding to a product from that side; 'comm' or 'acomm' results in commutation and anticommuta- tion superoperator respectively.
Note: This is a very general function to which direct calls are not usually required -- please use the (much friendlier) operator() function.