Conspicuous Presence of Higher Order Transitions in the Photoluminescence of InxGa1-xN/GaN Quantum Wells
For successive annealing stages the photoluminescence (PL) peaks of InXGa1-XN/GaN quantum wells (QWs) shift initially towards red which is followed by a blue. This phenomenon contradicts the usual monotonic blueshift. We have found that the phenomena can be explained properly only if we consider recombinations from the higher sub-bands to be present in the PL of the InXGa1-XN/GaN QWs, which is not usual. When a strong piezoelectric field exists across a QW, as encountered in InXGa1-XN/GaN QWs, the probability of optical transitions from higher sub-bands of the QW become more probable. In this paper this theory has been established from experimental results.
S. J. CHUA, J. H. TENG, O. WADA, R. DE LA RUE and X. H. TANG
D. Biswas et al., "Conspicuous Presence of Higher Order Transitions in the Photoluminescence of InxGa1-xN/GaN Quantum Wells", Advanced Materials Research, Vol. 31, pp. 62-64, 2008