Resonant tunneling times in superlattice structures

We present a rigorous and convenient approach for estimating the resonant states from the pole of the scattering matrix (reflection coefficient) in the complex energy plane and for determining the resonant tunneling time from the spacing of the energy doublets arising at resonance. The numerical calculation is much faster than numerical integration of the Schrodinger equation. When we apply this method to the coupling of two identical quantum wells, it is shown that the usual and naive estimation of resonant tunneling time through the Wentzel-Kramers-Brillouin method is invalid. (C) 1996 American Institute of Physics.