Terahertz intersubband absorption in non-polar m-plane AlGaN/GaN quantum wells

Journal Article · Mon Jul 14 00:00:00 EDT 2014 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4890611· OSTI ID:22311065

Edmunds, C.; Shao, J. ^[1]; Shirazi-HD, M. ^[2]; Manfra, M. J. ^[1]

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1. Physics Department, Purdue University, West Lafayette, Indiana 47907 (United States)
2. Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907 (United States)

We demonstrate THz intersubband absorption (15.6–26.1 meV) in m-plane AlGaN/GaN quantum wells. We find a trend of decreasing peak energy with increasing quantum well width, in agreement with theoretical expectations. However, a blue-shift of the transition energy of up to 14 meV was observed relative to the calculated values. This blue-shift is shown to decrease with decreasing charge density and is, therefore, attributed to many-body effects. Furthermore, a ∼40% reduction in the linewidth (from roughly 8 to 5 meV) was obtained by reducing the total sheet density and inserting undoped AlGaN layers that separate the wavefunctions from the ionized impurities in the barriers.

• OSTI ID: 22311065
• Journal Information: Applied Physics Letters, Vol. 105, Issue 2; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ABSORPTION
ALUMINIUM COMPOUNDS
CHARGE DENSITY
DENSITY
GALLIUM NITRIDES
IMPURITIES
LAYERS
MANY-BODY PROBLEM
QUANTUM WELLS
WAVE FUNCTIONS