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Title: Lasing in Zn-doped GaAs nanowires on an iron film
Abstract In this work, we demonstrate optically pumped lasing in highly Zn-doped GaAs nanowires (NWs) lying on an iron film. The conically shaped NWs are first covered with an 8 nm thick Al2O3film to prevent atmospheric oxidation and mitigate band-bending effects. Multimode and single-mode lasing have been observed for NWs with a length greater or smaller than 2μm, respectively. Finite difference time domain calculations reveal a weak electric field enhancement in the Al2O3layer at the NW/iron film interface for the lasing modes. The high Zn acceptor concentration in the NWs provides enhanced radiative efficiency and enables lasing on the iron film despite plasmonic losses. Our results open avenues for integrating NW lasers on ferromagnetic substrates to achieve new functionalities, such as magnetic field-induced modulation.  more » « less
Award ID(s):
2004768
PAR ID:
10441983
Author(s) / Creator(s):
; ; ; ; ; ; ;
Publisher / Repository:
IOP Publishing
Date Published:
Journal Name:
Nanotechnology
Volume:
34
Issue:
44
ISSN:
0957-4484
Page Range / eLocation ID:
Article No. 445201
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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