Simple Approach to N -Level Quantum Systems in Arbitrary Fields: The "Time-Slicer"
Joseph O. Hirschfelder, Robert W. Pyzalski · Physical Review Letters · 1985
A simple computational technique related to Feynman path integrals and linear control systems is derived for the dynamical properties of $N$-level model quantum mechanical systems in arbitrary classical fields: periodic, pulses, or sequences of pulses. Since the Hamiltonian is not required to be Hermitian, the effects of natural lifetimes and other relaxation parameters can be determined. The time-dependent Hamiltonian is approximated by a sequence of time-independent Hamiltonians ${\mathrm{H}}^{(n)}$.