Localization landscape theory of disorder in semiconductors I: Theory and modeling
Journal
Physical Review B
Journal Volume
95
Pages
654-659
Date Issued
2017
Author(s)
Abstract
We present here a model of carrier distribution and transport in semiconductor alloys accounting for quantum localization effects in disordered materials. This model is based on the recent development of a mathematical theory of quantum localization which introduces for each type of carrier a spatial function called localization landscape. These landscapes allow us to predict the localization regions of electron and hole quantum states, their corresponding energies, and the local densities of states. We show how the various outputs of these landscapes can be directly implemented into a drift-diffusion model of carrier transport and into the calculation of absorption/emission transitions. This creates a new computational model which accounts for disorder localization effects while also capturing two major effects of quantum mechanics, namely, the reduction of barrier height (tunneling effect) and the raising of energy ground states (quantum confinement effect), without having to solve the Schrödinger equation. Finally, this model is applied to several one-dimensional structures such as single quantum wells, ordered and disordered superlattices, or multiquantum wells, where comparisons with exact Schrödinger calculations demonstrate the excellent accuracy of the approximation provided by the landscape theory. © 2017 American Physical Society.
SDGs
Other Subjects
Computation theory; Functions; Ground state; One dimensional; Quantum chemistry; Semiconductor alloys; Semiconductor quantum wells; Carrier distributions; Disordered materials; Disordered superlattices; Drift-diffusion model; One-dimensional structure; Quantum confinement effects; Quantum localization; Theory and modeling; Quantum theory
Type
journal article