Analytical evidence of commuting resonance energy in correlated disorder trimer GaAs-AlxGa1–xAs superlattices

Abstract

Using the exact Airy function formalism and the transfer-matrix technique, we have numerically investigated the effect of structural and topological correlated disorder, introduced by triplet, on the miniband structure of the GaAs/AlxGa1–xAs superlattices. These systems exhibit a miniband of extended states, around a critical energy, lying to the typical structure of the trimer cell. The states close to this resonant energy consist of weakly localized states, while in band tails i.e., for negligible transmission, the states are strongly localized. This is evidence of the suppression of localization in the RTB superlattices. The extended states due to the basic cell (triple barrier) remain for correlated structural and topological disorder. However, the commuting extended state exists only in the correlated structural disorder, where the periodicity of the system is preserved. Commuting resonance energy is theoretically demonstrated in this paper, and the obtained values are in good agreement with the existing numerical results.