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  • A study of n-doping in self-catalyzed GaAsSb nanowires using GaTe dopant source and ensemble nanowire near-infrared photodetector
Title: A study of n-doping in self-catalyzed GaAsSb nanowires using GaTe dopant source and ensemble nanowire near-infrared photodetector
This work reports a comprehensive investigation of the effect of gallium telluride (GaTe) cell temperature variation (TGaTe) on the morphological, optical, and electrical properties of doped-GaAsSb nanowires (NWs) grown by Ga-assisted molecular beam epitaxy (MBE). These studies led to an optimum doping temperature of 550 °C for the growth of tellurium (Te)-doped GaAsSb NWs with the best optoelectronic and structural properties. Te incorporation resulted in a decrease in the aspect ratio of the NWs causing an increase in the Raman LO/TO vibrational mode intensity ratio, large PL emission with an exponential decay tail on the high energy side, promoting tunnel-assisted current conduction in ensemble NWs and significant photocurrent enhancement in the single nanowire. A Schottky barrier photodetector using Te-doped ensemble NWs with broad spectral range and a longer wavelength cutoff at ~ 1.2 µm was demonstrated. These photodetectors exhibited responsivity in the range of 580 – 620 A/W and detectivity of 1.2 – 3.8 × 1012 Jones. The doped GaAsSb NWs have the potential for further improvement, paving the path for high-performance near-infrared (NIR) photodetection applications.  more » « less
Award ID(s):
1832117
NSF-PAR ID:
10274159
Author(s) / Creator(s):
; ; ; ; ; ; ;
Date Published:
Journal Name:
Nanotechnology
Volume:
31
ISSN:
1361-6528
Page Range / eLocation ID:
505203
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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