scqubits.utils.spectrum_utils.matrix_element¶

scqubits.utils.spectrum_utils.matrix_element(state1, operator, state2)[source]¶

Calculate the matrix element <state1|operator|state2>.

Parameters:

state1 (Union[ndarray, Qobj]) – state vector/ket
state2 (Union[ndarray, Qobj]) – state vector/ket
operator (Union[ndarray, csc_matrix, Qobj]) – representation of an operator

Return type:

Union[float, complex]

Returns:

matrix element