Strong carrier localization and diminished quantum-confined Stark effect in ultra-thin high-indium-content InGaN quantum wells with violet light emission

• Published in: Applied physics letters Vol. 103; no. 22
• Main Authors: Ko, Suk-Min, Kwack, Ho-Sang, Park, Chunghyun, Yoo, Yang-Seok, Kwon, Soon-Yong, Jin Kim, Hee, Yoon, Euijoon, Si Dang, Le, Cho, Yong-Hoon
• Format: Journal Article
• Language: English
• Published: Melville American Institute of Physics 25-11-2013
• Subjects: Applied physics; CARRIERS; CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; EMISSION; GALLIUM NITRIDES; INDIUM; Indium gallium nitrides; Inhomogeneity; Light emission; Localization; QUANTUM EFFICIENCY; QUANTUM WELLS; STARK EFFECT; THICKNESS; Ultraviolet spectra; Variation; VISIBLE RADIATION
• ISSN: 0003-6951; 1077-3118
• DOI: 10.1063/1.4833917

Here, we report on the optical and structural characteristics of violet-light-emitting, ultra-thin, high-Indium-content (UTHI) InGaN/GaN multiple quantum wells (MQWs), and of conventional low-In-content MQWs, which both emit at similar emission energies though having different well thicknesses and In compositions. The spatial inhomogeneity of In content, and the potential fluctuation in high-efficiency UTHI MQWs were compared to those in the conventional low-In-content MQWs. We conclude that the UTHI InGaN MQWs are a promising structure for achieving better quantum efficiency in the visible and near-ultraviolet spectral range, owing to their strong carrier localization and reduced quantum-confined Stark effect.