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Title: Comparative analysis of selective area grown Ga- and N-polar InGaN/GaN nanowires for quantum emitters
In this paper, we report the molecular beam epitaxy-grown InGaN-quantum disks embedded within selective area epitaxy of GaN nanowires with both Ga- and N-polarities. A detailed comparative analysis of these two types of nanostructures is also provided. Compared to Ga-polar nanowires, N-polar nanowires are found to exhibit a higher vertical growth rate, flatter top, and reduced lateral overgrowth. InGaN quantum disk-related optical emission is observed from nanowires with both polarities; however, the N-polar structures inherently emit at longer wavelengths due to higher indium incorporation. Considering that N-polar nanowires offer more compelling geometry control compared to Ga-polar ones, we focus on the theoretical analysis of only N-polar structures to realize high-performance quantum emitters. A single nanowire-level analysis was performed, and the effects of nanowire diameter, taper length, and angle on guided modes, light extraction, and far-field emission were investigated. These findings highlight the importance of tailoring nanowire geometry and eventually optimizing the growth processes of III-nitride nanostructures.

 
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Award ID(s):
2034140 2011876
NSF-PAR ID:
10492654
Author(s) / Creator(s):
; ; ;  ; ; ;
Publisher / Repository:
American Institute of Physics
Date Published:
Journal Name:
AIP Advances
Volume:
14
Issue:
2
ISSN:
2158-3226
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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