  The resonant transmission of a moving particle which interacts with an
one-dimensional array of N delta-function potentials is investigated. A
suitable transfer matrix formulation is used to obtain the particle
transmission. We give the parameters for perfect tunnelling and the
transcendental equation for the quasi-bound state energies for N = 2, 3 and 4.
Conditions for perfect tunnelling and resonant transmission are discussed for
arrays with arbitrary N. A model to explain how the tunnelling energy filter
works in these systems is proposed here.
