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arXiv · 1406.1772

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

C. Edmunds·J. Shao·M. Shirazi-HD·M. J. Manfra·O. Malis
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Abstract

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.

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C. Edmunds, J. Shao, M. Shirazi-HD, M. J. Manfra, O. Malis. 2014-06-06. Terahertz intersubband absorption in non-polar m-plane AlGaN/GaN quantum wells. https://doi.org/10.1063/1.4890611

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