A fractional-dimensional space approach to the study of shallow-donor states in symmetric-coupled GaAs-Ga1-xAlxAs multiple quantum wells

摘要

The fractional-dimensional space approach is extended to study shallow-donor states in symmetric-coupled GaAs-Ga1 - xAlx As multiple quantum wells. In this scheme. the real anisotropic "shallow donor + multiple quantum well" semiconductor system is mapped for each shallow-donor state, into an effective fractional-dimensional isotropic environment, and the fractional dimension is essentially related to the anisotropy of the actual semiconductor system. Calculations within the fractional-dimensional space scheme were performed for the binding energies of Is-like shallow-donor states in various positions in symmetric-coupled double and triple GaAs-Ga1 - xAlxAs semiconductor quantum a wells, and for varying well and barrier thicknesses. Fractional-dimensional theoretical results an shown to be in good agreement with previous variational theoretical calculations. (C) 2001 Elsevier Science B.V. All rights reserved. [References: 32]