Impact ionization of excitons and donors in Al sub x Ga sub 1 minus x As/( n -type GaAs):Si quantum wells

Journal Article · Sun Mar 15 00:00:00 EST 1992 · Physical Review, B: Condensed Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.45.6263· OSTI ID:7070315

Weman, H; Treacy, G M ^[1]; Hjalmarson, H P ^[2]; Law, K K; Merz, J L; Gossard, A C ^[3]

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1. Center for Quantized Electronic Structures (QUEST), University of California, Santa Barbara, California 93106 (United States)
2. Sandia National Laboratory, Albuquerque, New Mexico 87185 (United States)
3. Department of Electrical and Computer Engineering and Materials Department, University of California, Santa Barbara, California 93106 (United States)

We have investigated the effect of a parallel electric field on the low-temperature photoluminescence from Al{sub {ital x}}Ga{sub 1{minus}{ital x}}As/({ital n}-type GaAs):Si quantum wells. We have studied the electric-field effect in a number of molecular-beam-epitaxy-grown Al{sub {ital x}}Ga{sub 1{minus}{ital x}}As/GaAs quantum-well structures doped with Si in the center of the well with well widths from 40 to 190 A. We observe sharp thresholds in the quenching of luminescence from the free and bound excitons at fields near a few tens of V/cm, accompanied by a sharp increase in the current. The actual threshold is critically dependent on the well width of the sample, which is qualitatively explained by the differences in carrier mobility. The mechanism responsible for the observed effects will be shown to be due to impact ionization of the excitons by the free carriers heated in the electric field.

• DOE Contract Number: AC04-76DP00789
• OSTI ID: 7070315
• Journal Information: Physical Review, B: Condensed Matter; (United States), Vol. 45:11; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM ARSENIDES
EXCITONS
IONIZATION
GALLIUM ARSENIDES
DOPED MATERIALS
N-TYPE CONDUCTORS
PHOTOLUMINESCENCE
SILICON ADDITIONS
ALLOYS
ALUMINIUM COMPOUNDS
ARSENIC COMPOUNDS
ARSENIDES
GALLIUM COMPOUNDS
LUMINESCENCE
MATERIALS
PNICTIDES
QUASI PARTICLES
SEMICONDUCTOR MATERIALS
SILICON ALLOYS
360606* - Other Materials- Physical Properties- (1992-)