Missing imaginary unit from the definition of the source operator
As far as I can say, in the documentation for the Source operator, an imaginary unit is missing in the definition: the expression given in the documentation should be multiplied by i. This should be there because otherwise the commutator would not be Hermitian. In the source code the commutator is in fact multiplied by i, if I'm understanding it correctly.
I also don't understand why is a Hermitian conjugate of the H_i taken for the definition of the source operator. Shouldn't the Hamiltonian matrix be Hermitian?