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arXiv · 2411.18175

Spectroscopic Signature of Local Alloy Fluctuations in InGaN/GaN Multi-Quantum-Disk Light Emitting Diode Heterostructures and Its Impact on the Optical Performance

Soumyadip Chatterjee·Subhranshu Sekhar Sahu·Kanchan Singh Rana·Swagata Bhunia·Dipankar Saha·Apurba Laha
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Abstract

Inhomogeneity-governed carrier localization has been investigated in three sets of InGaN/GaN multi-quantum-disk light-emitting diode (LED) structures grown by plasma-assisted molecular beam epitaxy (PAMBE) under different process conditions. A temperature-dependent study of the luminescence peak positions reveals that samples prepared under certain process conditions exhibit a thermal distribution of carriers from the localized states that show the typical S-shaped dependence in luminescence characteristics. The absence of an S-shaped nature in the other sample prepared with relatively higher In-flux infers a superior homogeneity in alloy composition. Further investigation manifested superior optical properties for the samples where the S-shape nature is found to be absent.

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Soumyadip Chatterjee, Subhranshu Sekhar Sahu, Kanchan Singh Rana, Swagata Bhunia, Dipankar Saha, Apurba Laha. 2024-11-27. Spectroscopic Signature of Local Alloy Fluctuations in InGaN/GaN Multi-Quantum-Disk Light Emitting Diode Heterostructures and Its Impact on the Optical Performance. https://doi.org/10.1016/j.jlumin.2025.121561

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