GaN quantum dots as optical transducers for chemical sensors

Journal Article · Mon Mar 16 04:00:00 EDT 2009 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.3100301· OSTI ID:21176050

Weidemann, O; Jegert, G; Stutzmann, M ^[1]; Kandaswamy, P K; Monroy, E ^[2]; Eickhoff, M ^[1]

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1. Walter Schottky Institut, Technische Universitaet Muenchen, Am Coulombwall 3, 85748 Garching (Germany)
2. CEA-CNRS group 'Nanophysique et semiconducteurs', INAC/SP2M/NPSC, CEA-Grenoble, 17 rue des Martyrs, 38054 Grenoble cedex 9 (France)

GaN/AlN quantum dots were investigated as optical transducers for field effect chemical sensors. The structures were synthesized by molecular-beam epitaxy and covered by a semitransparent catalytic Pt top contact. Due to the thin (3 nm) AlN barriers, the variation of the quantum dot photoluminescence with an external electric field along the [0001] axis is dominated by the tunneling current rather than by the quantum confined Stark effect. An increasing field results in a blueshift of the luminescence and a decreasing intensity. This effect is used to measure the optical response of quantum dot superlattices upon exposure to molecular hydrogen.

• OSTI ID: 21176050
• Journal Information: Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 11 Vol. 94; ISSN APPLAB; ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM NITRIDES
CRYSTAL GROWTH
ELECTRIC FIELDS
GALLIUM NITRIDES
HYDROGEN
MOLECULAR BEAM EPITAXY
PHOTOLUMINESCENCE
PLATINUM
QUANTUM DOTS
SEMICONDUCTOR MATERIALS
SENSORS
STARK EFFECT
SUPERLATTICES
TRANSDUCERS
TUNNEL EFFECT