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Title: Low voltage drop AlGaN UV-A laser structures with transparent tunnel junctions and optimized quantum wells
Abstract

This paper presents the design, material growth and fabrication of AlGaN laser structures grown by plasma-assisted molecular beam epitaxy. Considering hole transport to be the major challenge, our ultraviolet-A diode laser structures have a compositionally graded transparent tunnel junction, resulting in superior hole injection and a low contact resistance. By optimizing active region thickness, a five-fold improvement in photoluminescence intensity is obtained compared to that of our own non-optimized test structures. The electrical and optical characteristics of processed devices demonstrate only spontaneous emission with a peak wavelength at 354 nm. The devices operate up to a continuous-wave current density of 11.1 kA cm−2at room temperature, which is the highest reported for laser structures grown on AlGaN templates. Additionally, they exhibit a record-low voltage drop of 8.5 V to achieve this current density.

 
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Award ID(s):
2034140
NSF-PAR ID:
10470997
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Publisher / Repository:
IOP Publishing
Date Published:
Journal Name:
Journal of Physics D: Applied Physics
Volume:
57
Issue:
3
ISSN:
0022-3727
Format(s):
Medium: X Size: Article No. 035105
Size(s):
["Article No. 035105"]
Sponsoring Org:
National Science Foundation
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