Expmint.m

Computes matrix exponential integrals of the following general type:

            Integrate[expm(-i*A*t)*B*expm(i*C*t),{t,0,T}]

Matrix A must be Hermitian. For further information see the paper by Charles van Loan (http://dx.doi.org/10.1109/TAC.1978.1101743). Syntax:

                    R=expmint(spin_system,A,B,C,T)