Disorder effects on tunneling through one-dimensional double-barrier quantum-well structures: A coherent-potential approximation

Abstract
We present a formalism for studying the disorder effects on electron tunneling through one-dimensional double-barrier quantum-well structures based on the coherent-potential approximation. This formalism enables us to calculate the configuration-averaged transmission coefficients in a nonperturbative way. It is shown that elastic scattering reduces and broadens the resonance peak, and also destroys its Lorentzian behavior. For sharp resonance structures, the transmission coefficient directly reflects the structures in the density of states within the well. The result obtained using this method agrees well with direct numerical simulation.