Excitonic localization at macrostep edges in AlGaN/AlGaN multiple quantum wells. (April 2017)

• Record Type: Journal Article
• Authors: Hou, Mengjun; Qin, Zhixin; Zhang, Lisheng; Han, Tianyang; Wang, Mingxing; Xu, Fujun; Wang, Xinqiang; Yu, Tongjun; Fang, Zheyu; Shen, Bo
• Is Part Of: Superlattices and microstructures. Volume 104(2017)
• Page Start: 397
• Page End: 401
• Publication Date: 2017-04
• Subjects: AlGaN -- Macrostep edge -- Quantum wires; Superlattices as materials -- Periodicals; Microstructure -- Periodicals; Semiconductors -- Periodicals; Superréseaux -- Périodiques; Microstructure (Physique) -- Périodiques; Semiconducteurs -- Périodiques; 621.38152
• DOI: 10.1016/j.spmi.2017.02.051
• Languages: English
• ISSNs: 0749-6036

Abstract

Abstract: Double peaks at wavelength of 276 and 290 nm are observed for AlGaN/AlGaN multiple quantum wells (MQWs). Cathodoluminescence (CL) mappings identify that the emission at 290 nm originates from the macrostep edges. Potential minima induced by local variation of QW thickness and Ga incorporation are found along the step edges, where quantum wires (QWRs) are formed. The lateral advance rate of macrostep (∼310 nm/h) is obtained by investigating the distribution of QWRs. Temperature-dependent CL spectrum suggest that thermal quenching for 290 nm emission is dramatically suppressed compared with that for conventional QWs emission, which shows excitonic localization characteristics of QWRs. Highlights: The origins of the double peaks for AlGaN multiple quantum wells (MQWs) are investigated. Quantum wires (QWRs) structures are observed along the macrostep edges. The lateral advance rate of macrostep is obtained. The optical properties of QWs and QWRs are studied.