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Title: High-Q lattice mode matched structural resonances in terahertz metasurfaces

Abstract

The quality (Q) factor of metamaterial resonances is limited by the radiative and non-radiative losses. At terahertz frequencies, the dominant loss channel is radiative in nature since the non-radiative losses are low due to high conductivity of metals. Radiative losses could be suppressed by engineering the meta-atom structure. However, such suppression usually occurs at the fundamental resonance mode which is typically a closed mode resonance such as an inductive-capacitive resonance or a Fano resonance. Here, we report an order of magnitude enhancement in Q factor of all the structural eigenresonances of a split-ring resonator fueled by the lattice mode matching. We match the fundamental order diffractive mode to each of the odd and even eigenresonances, thus leading to a tremendous line-narrowing of all the resonances. Such precise tailoring and control of the structural resonances in a metasurface lattice could have potential applications in low-loss devices, sensing, and design of high-Q metamaterial cavities.

Authors:
;  [1];  [2];  [3]
  1. School of Electrical and Computer Engineering, Oklahoma State University, Stillwater, Oklahoma 74078 (United States)
  2. Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371 (Singapore)
  3. (Singapore)
Publication Date:
OSTI Identifier:
22590588
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 109; Journal Issue: 2; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ATOMS; DESIGN; LINE NARROWING; LOSSES; METALS; METAMATERIALS; RESONANCE; SPLIT-RING RESONATORS

Citation Formats

Xu, Ningning, Zhang, Weili, E-mail: weili.zhang@okstate.edu, Singh, Ranjan, E-mail: ranjans@ntu.edu.sg, and Centre for Disruptive Photonic Technologies, The Photonics Institute, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798. High-Q lattice mode matched structural resonances in terahertz metasurfaces. United States: N. p., 2016. Web. doi:10.1063/1.4958730.
Xu, Ningning, Zhang, Weili, E-mail: weili.zhang@okstate.edu, Singh, Ranjan, E-mail: ranjans@ntu.edu.sg, & Centre for Disruptive Photonic Technologies, The Photonics Institute, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798. High-Q lattice mode matched structural resonances in terahertz metasurfaces. United States. doi:10.1063/1.4958730.
Xu, Ningning, Zhang, Weili, E-mail: weili.zhang@okstate.edu, Singh, Ranjan, E-mail: ranjans@ntu.edu.sg, and Centre for Disruptive Photonic Technologies, The Photonics Institute, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798. 2016. "High-Q lattice mode matched structural resonances in terahertz metasurfaces". United States. doi:10.1063/1.4958730.
@article{osti_22590588,
title = {High-Q lattice mode matched structural resonances in terahertz metasurfaces},
author = {Xu, Ningning and Zhang, Weili, E-mail: weili.zhang@okstate.edu and Singh, Ranjan, E-mail: ranjans@ntu.edu.sg and Centre for Disruptive Photonic Technologies, The Photonics Institute, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798},
abstractNote = {The quality (Q) factor of metamaterial resonances is limited by the radiative and non-radiative losses. At terahertz frequencies, the dominant loss channel is radiative in nature since the non-radiative losses are low due to high conductivity of metals. Radiative losses could be suppressed by engineering the meta-atom structure. However, such suppression usually occurs at the fundamental resonance mode which is typically a closed mode resonance such as an inductive-capacitive resonance or a Fano resonance. Here, we report an order of magnitude enhancement in Q factor of all the structural eigenresonances of a split-ring resonator fueled by the lattice mode matching. We match the fundamental order diffractive mode to each of the odd and even eigenresonances, thus leading to a tremendous line-narrowing of all the resonances. Such precise tailoring and control of the structural resonances in a metasurface lattice could have potential applications in low-loss devices, sensing, and design of high-Q metamaterial cavities.},
doi = {10.1063/1.4958730},
journal = {Applied Physics Letters},
number = 2,
volume = 109,
place = {United States},
year = 2016,
month = 7
}
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