The University of Southampton
University of Southampton Institutional Repository

Controlling light localization with nanophotonic metamaterials

Controlling light localization with nanophotonic metamaterials
Controlling light localization with nanophotonic metamaterials
Light localization plays an important role in developing high resolution imaging and precision technologies in nanophotonics. In order to create and control nanoscale light localizations, this thesis has investigated into two research topics with different types of nanophotonic metamaterials: precise control of near-field light localizations and subwavelength light concentration beyond the near field.

For the first topic, (i) I have demonstrated for the first time that a planar fish-scale metamaterial can be used as a controllable template for nanoscale light localizations. By tuning the polarization and wavelength of an incident light beam, the positions of energy hot-spots on the landscape of the metamaterial can be efficiently controlled. Moreover, it has been found that the locations of the hot-spots show a high correlation with the nanostructure, the unit cell size, and the dipole absorption resonance of the fish-scale metamaterial.

In an array of discrete asymmetrically split-ring meta-molecules system, (ii) I have also demonstrated for the first time that the well-isolated subwavelength energy hot-spots can be created and positioned on the metamaterial landscape by the coherent control of a monochromatic continuous light beam with a spatially modulated phase profile. Due to the strong optically induced interactions between meta-molecules, a well-isolated energy hot-spot of a fraction of wavelength has been created. By simply tailoring the phase profile, the hot-spot positions on the metamaterial can be prescribed and moved at will from one meta-molecule to another in a digital fashion with an accurate moving step around lambda/2. In my experiments, (iii) I have integrated a scanning near-field optical microscope and a spatial light modulator to demonstrate the coherent control process. Via this approach, an energy concentration on the nanoscale and accurate control of the energy hot-spots have been achieved.

For the second topic, based on optical super-oscillation, (iv) I have first created an isolated focused spot by using a super-oscillating binary masks with radially symmetric quasi-periodic arrangement of nanoholes. The well-isolated focused spot around 0.45 lambda has been acquired in a wide field of view about 90 lambda. (v) Discovering another exploitation of nanohole arrays, it has been shown that a quasi-periodic nanohole array can be used as a conventional lens with a high numerical aperture around 0.89.
University of Southampton
Kao, Tsung-Sheng
92b68d1b-1501-4f42-9707-0f9f90c0ef16
Kao, Tsung-Sheng
92b68d1b-1501-4f42-9707-0f9f90c0ef16
Zheludev, Nikolay I.
32fb6af7-97e4-4d11-bca6-805745e40cc6
Rogers, E.T.F.
b92cc8ab-0d91-4b2e-b5c7-8a2f490a36a2

Kao, Tsung-Sheng (2012) Controlling light localization with nanophotonic metamaterials. University of Southampton, Faculty of Physical and Applied Sciences, Doctoral Thesis, 240pp.

Record type: Thesis (Doctoral)

Abstract

Light localization plays an important role in developing high resolution imaging and precision technologies in nanophotonics. In order to create and control nanoscale light localizations, this thesis has investigated into two research topics with different types of nanophotonic metamaterials: precise control of near-field light localizations and subwavelength light concentration beyond the near field.

For the first topic, (i) I have demonstrated for the first time that a planar fish-scale metamaterial can be used as a controllable template for nanoscale light localizations. By tuning the polarization and wavelength of an incident light beam, the positions of energy hot-spots on the landscape of the metamaterial can be efficiently controlled. Moreover, it has been found that the locations of the hot-spots show a high correlation with the nanostructure, the unit cell size, and the dipole absorption resonance of the fish-scale metamaterial.

In an array of discrete asymmetrically split-ring meta-molecules system, (ii) I have also demonstrated for the first time that the well-isolated subwavelength energy hot-spots can be created and positioned on the metamaterial landscape by the coherent control of a monochromatic continuous light beam with a spatially modulated phase profile. Due to the strong optically induced interactions between meta-molecules, a well-isolated energy hot-spot of a fraction of wavelength has been created. By simply tailoring the phase profile, the hot-spot positions on the metamaterial can be prescribed and moved at will from one meta-molecule to another in a digital fashion with an accurate moving step around lambda/2. In my experiments, (iii) I have integrated a scanning near-field optical microscope and a spatial light modulator to demonstrate the coherent control process. Via this approach, an energy concentration on the nanoscale and accurate control of the energy hot-spots have been achieved.

For the second topic, based on optical super-oscillation, (iv) I have first created an isolated focused spot by using a super-oscillating binary masks with radially symmetric quasi-periodic arrangement of nanoholes. The well-isolated focused spot around 0.45 lambda has been acquired in a wide field of view about 90 lambda. (v) Discovering another exploitation of nanohole arrays, it has been shown that a quasi-periodic nanohole array can be used as a conventional lens with a high numerical aperture around 0.89.

Text
thesis_tsk_final.pdf - Version of Record
Available under License University of Southampton Thesis Licence.
Download (50MB)

More information

Published date: July 2012
Organisations: University of Southampton, Optoelectronics Research Centre

Identifiers

Local EPrints ID: 341198
URI: http://eprints.soton.ac.uk/id/eprint/341198
PURE UUID: c586e55d-b49c-47da-a9ae-84aa78c4e341
ORCID for Nikolay I. Zheludev: ORCID iD orcid.org/0000-0002-1013-6636

Catalogue record

Date deposited: 03 Sep 2012 15:30
Last modified: 15 Mar 2024 02:44

Export record

Contributors

Author: Tsung-Sheng Kao
Thesis advisor: Nikolay I. Zheludev ORCID iD
Thesis advisor: E.T.F. Rogers

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×