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Intersubband Transition in GaN/InGaN Multiple Quantum Wells
1State Key Laboratory of Artificial Microstructure and Mesoscopic Physics, School of Physics, Peking University, Beijing 100871, China.
Scientific Reports
|June 20, 2015
Summary
Researchers developed new Gallium Nitride/Indium Gallium Nitride quantum wells for infrared devices. These novel structures show tunable intersubband transitions (ISBT) in the 3-5 μm range, crucial for atmospheric sensing applications.
Area of Science:
- Materials Science
- Optoelectronics
- Solid State Physics
Background:
- III-nitride materials are promising for optoelectronic devices.
- Infrared detectors are essential for various applications, including atmospheric monitoring.
- Intersubband transitions (ISBT) offer a pathway for infrared light absorption.
Purpose of the Study:
- To experimentally realize high-quality GaN/In0.15Ga0.85N multiple quantum wells for ISBT.
- To investigate the potential of these quantum wells for III-nitride infrared device applications.
- To explore the tunability of ISBT absorption wavelengths by controlling quantum well width.
Main Methods:
- Growth temperature controlled epitaxy was used to fabricate GaN/In0.15Ga0.85N multiple quantum wells.
- Photo-absorption spectroscopy was employed to detect ISBT.
- Quantum well width was systematically varied to study its effect on absorption wavelength.
Main Results:
- High-quality GaN/In0.15Ga0.85N multiple quantum wells were successfully fabricated.
- Photo-absorption from ISBT was observed in the 3-5 μm infrared atmospheric window.
- A non-monotonic shift in the central absorption wavelength was observed with increasing quantum well thickness, attributed to polarization-induced asymmetry.
Conclusions:
- GaN/In0.15Ga0.85N quantum wells are viable candidates for III-nitride based infrared devices.
- The ISBT wavelength can be modulated by quantum well width, offering design flexibility.
- Polarization effects significantly influence the ISBT characteristics in these structures.
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