Pressure dependence of optical transitions in In{sub 0.15}Ga{sub 0.85}N/GaN multiple quantum wells

Journal Article · Thu Oct 01 04:00:00 EDT 1998 · Physical Review, B: Condensed Matter

DOI:https://doi.org/10.1103/PhysRevB.58.R10191· OSTI ID:326851

Shan, W; Ager, J.W. III, and; Walukiewicz, W ^[1]; Haller, E E ^[2]; McCluskey, M D; Johnson, N M; Bour, D P ^[3]

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1. Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California, 94720 (United States)
2. Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)
3. Xerox Palo Alto Research Center, 3333 Coyote Hill Road, Palo Alto, California, 94304 (United States)

The effects of hydrostatic pressure on optical transitions in In{sub 0.15}Ga{sub 0.85}N/GaN multiple quantum wells (MQW{close_quote}s) have been studied. The optical transition associated with confined electron and hole states in the MQW{close_quote}s was found to shift linearly to higher energy with pressure but exhibit a significantly weaker pressure dependence compared to bulklike thick epitaxial-layer samples. Similar pressure coefficients obtained by both photomodulation and photoluminescence measurements rule out the possibility of the transition involving localized states deep in the band gap. We found that the difference in the compressibility of In{sub x}Ga{sub 1{minus}x}N and GaN induces a tensile strain in the compressively strained In{sub x}Ga{sub 1{minus}x}N well layers, partially compensating the externally applied hydrostatic pressure. This mechanical effect is primarily responsible for the smaller pressure dependence of the optical transitions in the In{sub x}Ga{sub 1{minus}x}N/GaN MQW{close_quote}s. In addition, the pressure-dependent measurements allow us to identify a spectral feature observed at an energy below the GaN band gap. We conclude that this feature is due to transitions from ionized Mg acceptor states to the conduction band in the {ital p}-type GaN cladding layer rather than a confined transition in the MQW{close_quote}s. {copyright} {ital 1998} {ital The American Physical Society}

• OSTI ID: 326851
• Journal Information: Physical Review, B: Condensed Matter, Journal Name: Physical Review, B: Condensed Matter Journal Issue: 16 Vol. 58; ISSN 0163-1829; ISSN PRBMDO
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
66 PHYSICS
COMPRESSIBILITY
ENERGY GAP
ENERGY-LEVEL TRANSITIONS
GALLIUM COMPOUNDS
GALLIUM NITRIDES
HOLES
INDIUM COMPOUNDS
INDIUM NITRIDES
LAYERS
PHOTOLUMINESCENCE
SUPERLATTICES