Physics and polarization characteristics of 298 nm AlN-delta-GaN quantum well ultraviolet light-emitting diodes
Abstract
This work investigates the physics and polarization characteristics of 298 nm AlN-delta-GaN quantum well (QW) ultraviolet (UV) light-emitting diodes (LEDs). The physics analysis shows that the use of the AlN-delta-GaN QW structure can ensure dominant conduction band (C) to heavy-hole (HH) subband transition and significantly improve the electron and top HH subband wave function overlap. As a result, up to 30-times enhancement in the transverse-electric (TE)-polarized spontaneous emission rate of the proposed structure can be obtained as compared to a conventional AlGaN QW structure. The polarization properties of molecular beam epitaxy-grown AlN/GaN QW-like UV LEDs, which consist of 3–4 monolayer (QW-like) delta-GaN layers sandwiched by 2.5-nm AlN sub-QW layers, are investigated in this study. The polarization-dependent electroluminescence measurement results are consistent with the theoretical analysis. Specifically, the TE-polarized emission intensity is measured to be much larger than the transverse-magnetic emission, indicating significant potential for our proposed QW structure for high-efficiency TE-polarized mid-UV LEDs.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Feb 13, 2017
- Source ID
- 10.1063/1.4976203
Entities
People
- Debdeep Jena
- Fengwei Liu
- Huili Grace Xing
- Jai Verma
- Jing Zhang
- S. M. Islam
- Yu Kee Ooi
Organizations
- Cornell University
- National Science Foundation
- Office of Naval Research
- Rochester Institute of Technology
- University of Notre Dame