Quasiparticle excitations in GaAs[sub 1[minus][ital x]]N[sub [ital x]] and AlAs[sub 1[minus][ital x]]N[sub [ital x]] ordered alloys

Journal Article · Wed Feb 15 00:00:00 EST 1995 · Physical Review, B: Condensed Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.51.4343· OSTI ID:6869771

Rubio, A; Cohen, M L ^[1]

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1. Department of Physics, University of California at Berkeley, and Materials Sciences Division, Lawrence Berkeley Laboratory, Berkeley, California 94720 (United States)

We have performed a quasiparticle study of the fundamental excitations in ordered alloys of III-V semiconductors, GaAs[sub 1[minus][ital x]]N[sub [ital x]] and AlAs[sub 1[minus][ital x]]N[sub [ital x]]. The experimentally observed anomalous redshift in GaAs[sub 1[minus][ital x]]N[sub [ital x]] of the direct band edge is explained here by effects arising from the 20% lattice mismatch. The fact that the bottom of the conduction band is mainly dominated by nitrogen leads to a large reduction of the fundamental gap at [Gamma] as the volume increases. This reduction continues until the charge density begins to locate on the arsenic site. Based on this simple scenario, we predict that a similar redshift may be observed in the indirect gap AlAs[sub 1[minus][ital x]]N[sub [ital x]] alloys. Also an indirect to direct band-gap transition will be observed for intermediate N concentrations. The possibility of closing the band gap is discussed in terms of the quasiparticle results.

• DOE Contract Number: AC03-76SF00098
• OSTI ID: 6869771
• Journal Information: Physical Review, B: Condensed Matter; (United States), Vol. 51:7; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALUMINIUM ARSENIDES
BAND THEORY
PHOTOLUMINESCENCE
GALLIUM ARSENIDES
COLLECTIVE EXCITATIONS
NITROGEN ADDITIONS
QUASI PARTICLES
SUBSTOICHIOMETRY
ALLOYS
ALUMINIUM COMPOUNDS
ARSENIC COMPOUNDS
ARSENIDES
ENERGY-LEVEL TRANSITIONS
EXCITATION
GALLIUM COMPOUNDS
LUMINESCENCE
PNICTIDES
360606* - Other Materials- Physical Properties- (1992-)
665000 - Physics of Condensed Matter- (1992-)