Theoretical studies on in-plane polarization characteristics of (112¯0) nonpolar InGaN/GaN quantum-well structures grown on InGaN substrates

• Published in: Journal of the Korean Physical Society 2022, 81(1), , pp.45-48
• Main Authors: Park, Seoung-Hwan, Shim, Jong-In, Shin, Dong-Soo
• Format: Article
• Language: English
• Subjects: Anisotropy; Gallium nitrides; Indium gallium nitrides; Linear polarization; Mathematical and Computational Physics; Original Paper - Condensed Matter; Particle and Nuclear Physics; Physics; Physics and Astronomy; Polarization characteristics; Quantum wells; Substrates; Theoretical; 물리학
• ISSN: 0374-4884; 1976-8524
• DOI: 10.1007/s40042-022-00489-9

The in-plane polarization characteristics of nonpolar (11 2 ¯ 0) In x Ga 1 - x N/GaN ( x = 0.2 ) quantum-well (QW) structures are investigated as a function of In content in In y Ga 1 - y N substrates by using the multiband effective-mass theory. States constituting the topmost valence subband change from | Y ′ > -like to | Z ′ > -like as the In content in the InGaN substrate increases. In the case of the QW structure grown on a conventional GaN substrate ( y = 0.0 ), the y ′ -polarized matrix element is much larger than the x ′ -polarized matrix element. However, the y ′ -polarized matrix element rapidly decreases with increasing y content in the InGaN substrate and becomes similar to the x ′ -polarized matrix element. As a result, the magnitude of the in-plane optical anisotropy becomes smaller for QW structures with higher substrate In content because both x ′ - and y ′ -polarized emission peaks are similar to each other.