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Optical far-field extinction of a single GaAs nanowire towards in situ size control of aerotaxy nanowire growth

Chen, Yang LU ; Anttu, Nicklas LU ; Sivakumar, Sudhakar LU ; Gompou, Eleni and Magnusson, Martin H. LU (2020) In Nanotechnology 31(13).
Abstract

A substrate-free approach of semiconductor nanowire growth has been achieved by the aerotaxy technique previously. In this work, we propose an in situ method to monitor the size of nanowires through non-destructive optical-extinction measurements. Our work aims to build a theoretical look-up database of extinction spectra for a single nanowire of varying dimensions. We describe the origin of possible peaks in the spectra, for example due to nanowire-length dependent Fabry-Perot resonances and nanowire-diameter dependent TM and TE mode resonances. Furthermore, we show that the Au catalyst on top of the nanowire can be ignored in the simulations when the volume of the nanowire is an order of magnitude larger than that of the Au catalyst... (More)

A substrate-free approach of semiconductor nanowire growth has been achieved by the aerotaxy technique previously. In this work, we propose an in situ method to monitor the size of nanowires through non-destructive optical-extinction measurements. Our work aims to build a theoretical look-up database of extinction spectra for a single nanowire of varying dimensions. We describe the origin of possible peaks in the spectra, for example due to nanowire-length dependent Fabry-Perot resonances and nanowire-diameter dependent TM and TE mode resonances. Furthermore, we show that the Au catalyst on top of the nanowire can be ignored in the simulations when the volume of the nanowire is an order of magnitude larger than that of the Au catalyst and the diameter is small compared to the incident wavelength. For the calculation of the extinction spectra, we use the finite element method, the discrete dipole approximation and the Mie theory. To compare with experimental measurements of randomly oriented nanowires, we perform an averaging over nanowire orientation for the modeled results. However, in the experiments, nanowires are accumulating on the quartz window of the measurement setup, which leads to increasing uncertainty in the comparison with the experimental extinction spectra. This uncertainty can be eliminated by considering both a sparse and a dense collection of nanowires on the quartz window in the optical simulations. Finally, we create a database of extinction spectra for a GaAs nanowire of varying diameters and lengths. This database can be used to estimate the diameter and the length of the nanowires by comparing the position of a peak and the peak-to-shoulder difference in the extinction spectrum. Possible tapering of nanowires can be monitored through the appearance of an additional peak at a wavelength of 700-800 nm.

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Please use this url to cite or link to this publication:
author
; ; ; and
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
semiconductor nanowire, light scattering, aerotaxy growth
in
Nanotechnology
volume
31
issue
13
publisher
IOP Publishing
external identifiers
  • scopus:85077937603
  • pmid:31917683
ISSN
0957-4484
DOI
10.1088/1361-6528/ab5fe4
language
English
LU publication?
yes
id
f9487a25-ccf2-4248-9cb4-f340f999a2a1
date added to LUP
2020-01-30 16:02:06
date last changed
2024-05-29 07:06:06
@article{f9487a25-ccf2-4248-9cb4-f340f999a2a1,
  abstract     = {{<p>A substrate-free approach of semiconductor nanowire growth has been achieved by the aerotaxy technique previously. In this work, we propose an in situ method to monitor the size of nanowires through non-destructive optical-extinction measurements. Our work aims to build a theoretical look-up database of extinction spectra for a single nanowire of varying dimensions. We describe the origin of possible peaks in the spectra, for example due to nanowire-length dependent Fabry-Perot resonances and nanowire-diameter dependent TM and TE mode resonances. Furthermore, we show that the Au catalyst on top of the nanowire can be ignored in the simulations when the volume of the nanowire is an order of magnitude larger than that of the Au catalyst and the diameter is small compared to the incident wavelength. For the calculation of the extinction spectra, we use the finite element method, the discrete dipole approximation and the Mie theory. To compare with experimental measurements of randomly oriented nanowires, we perform an averaging over nanowire orientation for the modeled results. However, in the experiments, nanowires are accumulating on the quartz window of the measurement setup, which leads to increasing uncertainty in the comparison with the experimental extinction spectra. This uncertainty can be eliminated by considering both a sparse and a dense collection of nanowires on the quartz window in the optical simulations. Finally, we create a database of extinction spectra for a GaAs nanowire of varying diameters and lengths. This database can be used to estimate the diameter and the length of the nanowires by comparing the position of a peak and the peak-to-shoulder difference in the extinction spectrum. Possible tapering of nanowires can be monitored through the appearance of an additional peak at a wavelength of 700-800 nm.</p>}},
  author       = {{Chen, Yang and Anttu, Nicklas and Sivakumar, Sudhakar and Gompou, Eleni and Magnusson, Martin H.}},
  issn         = {{0957-4484}},
  keywords     = {{semiconductor nanowire; light scattering; aerotaxy growth}},
  language     = {{eng}},
  month        = {{01}},
  number       = {{13}},
  publisher    = {{IOP Publishing}},
  series       = {{Nanotechnology}},
  title        = {{Optical far-field extinction of a single GaAs nanowire towards in situ size control of aerotaxy nanowire growth}},
  url          = {{http://dx.doi.org/10.1088/1361-6528/ab5fe4}},
  doi          = {{10.1088/1361-6528/ab5fe4}},
  volume       = {{31}},
  year         = {{2020}},
}