Theoretical and experimental analysis of the photoluminescence and photoluminescence excitation spectroscopy spectra of m-plane InGaN/GaN quantum wells
Tanner, Daniel S. P.
O'Reilly, Eoin P.
Caro, Miguel A.
Griffiths, J. T.
Kappers, M. J.
Oliver, R. A.
Humphreys, C. J.
We present a combined theoretical and experimental analysis of the optical properties of m-plane InGaN/GaN quantum wells. The sample was studied by photoluminescence and photoluminescence excitation spectroscopy at low temperature. The spectra show a large Stokes shift between the lowest exciton peak in the excitation spectra and the peak of the photoluminescence spectrum. This behavior is indicative of strong carrier localization effects. These experimental results are complemented by tight-binding calculations, accounting for random alloy fluctuations and Coulomb effects. The theoretical data explain the main features of the experimental spectra. Moreover, by comparison with calculations based on a virtual crystal approximation, the importance of carrier localization effects due to random alloy fluctuations is explicitly shown.
Gallium compounds , III-V semiconductors , Indium compounds , Localised states , Photoluminescence , Semiconductor quantum wells , Tight-binding calculations , Wide band gap semiconductors , Excitons , Localization effects , Visible spectra
Schulz, S., Tanner, D. S. P., O'Reilly, E. P., Caro, M. A., Tang, F., Griffiths, J. T., Oehler, F., Kappers, M. J., Oliver, R. A., Humphreys, C. J., Sutherland, D., Davies, M. J. and Dawson, P. (2016) 'Theoretical and experimental analysis of the photoluminescence and photoluminescence excitation spectroscopy spectra of m-plane InGaN/GaN quantum wells', Applied Physics Letters, 109(22), pp. 223102. doi:10.1063/1.4968591
© 2016, AIP Publishing. This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. The following article appeared in Applied Physics Letters 109, 223102 (2016) and may be found at http://aip.scitation.org/doi/abs/10.1063/1.4968591