Energy spectra of shallow donors and acceptors in GaAs/sub 1-x/Al/sub x/As superlattices

Conference · Mon Jun 01 00:00:00 EDT 1987

OSTI ID:6183694

Oliveira, L E; Falicov, L M

The energy spectra of shallow donors and acceptors in GaAs-Ga/sub 1-x/Al/sub x/As quantum-well structures have been calculated. The binding energies of the impurities were obtained within a variational calculation in the effective-mass approximation. Calculations were performed for various types of impurity as functions of the position of the impurity in a GaAs quantum well of infinite depth and for various slab thicknesses. The effect of the spatially dependent screening is modeled with a function of the form epsilon/sup -1/(r) = epsilon/sub 0//sup -1/ + (1 - epsilon/sub 0//sup -1/) e/sup -r/a/, with a screening parameter a approx. =1.1 a.u. characteristic of bulk GaAs. Results are compared with Bastard's theory, which is based on a constant epsilon/sub 0/ screening, and it is found that spatially dependent screening effects can be quite important for all acceptors in GaAs quantum wells over a large range of slab thicknesses. Calculated results with improved statistics are in quantitative agreement with experimental data.

• Research Organization: Lawrence Berkeley Lab., CA (USA); Universidade Estadual de Campinas (Brazil). Inst. de Fisica
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 6183694
• Report Number(s): LBL-23492; CONF-870276-2; ON: DE87014120
• Resource Relation: Conference: 3. Brazilian school of semiconductor physics, Campinas, Brazil, 16 Feb 1987; Other Information: Portions of this document are illegible in microfiche products
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
42 ENGINEERING
ALUMINIUM ARSENIDES
ELECTRONIC STRUCTURE
GALLIUM ARSENIDES
HETEROJUNCTIONS
BINDING ENERGY
ELECTRONS
IMPURITIES
SUPERLATTICES
VALENCE
ALUMINIUM COMPOUNDS
ARSENIC COMPOUNDS
ARSENIDES
ELEMENTARY PARTICLES
ENERGY
FERMIONS
GALLIUM COMPOUNDS
JUNCTIONS
LEPTONS
PNICTIDES
SEMICONDUCTOR JUNCTIONS
360603* - Materials- Properties
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