Feshbach projection formalism for transmission through a time-periodic potential

The Feshbach projection formalism is applied to consider quantum transmission through a tight-binding wire subject to a time-periodic potential. The wire is coupled with two leads via the coupling constant v{C}. The periodicity of the potential implies an additional temporal dimension that reduces the problem to stationary transmission through an effectively two-dimensional lattice system. The non-Hermitian effective Hamiltonian is formulated. This allows us to trace the redistribution of resonance positions and resonance widths with the growth of v{C} from the weak-coupling to the strong-coupling regime.