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Title: Splitting of magnetic dipole modes in anisotropic TiO 2 micro-spheres: Splitting of magnetic dipole modes in anisotropic TiO 2 micro-spheres

Abstract

Monocrystalline titanium dioxide (TiO 2) micro-spheres support two orthogonal magnetic dipole modes at terahertz (THz) frequencies due to strong dielectric anisotropy. For the first time, we experimentally detected the splitting of the first Mie mode in spheres of radii inline imagem through near-field time-domain THz spectroscopy. By fitting the Fano lineshape model to the experimentally obtained spectra of the electric field detected by the sub-wavelength aperture probe, we found that the magnetic dipole resonances in TiO 2 spheres have narrow linewidths of only tens of gigahertz. Lastly, anisotropic TiO 2 micro-resonators can be used to enhance the interplay of magnetic and electric dipole resonances in the emerging THz all-dielectric metamaterial technology.

Authors:
 [1];  [2];  [3];  [3];  [4];  [4];  [4];  [4];  [5]
  1. King's College London, London (United Kingdom); UCL, London (United Kingdom); ITMO University, St. Petersburg (Russia)
  2. Academy of Sciences of the Czech Republic (ASCR), Prague (Czech Republic). Inst. of Physics
  3. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
  4. Univ. of Bordeaux, Pessac (France)
  5. UCL, London (United Kingdom); Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Publication Date:
Research Org.:
Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1259675
Report Number(s):
SAND-2016-3103J
Journal ID: ISSN 1863-8880; 637692
Grant/Contract Number:
AC04-94AL85000
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Laser & Photonics Reviews
Additional Journal Information:
Journal Name: Laser & Photonics Reviews; Journal ID: ISSN 1863-8880
Publisher:
Wiley
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; Terahertz spectroscopy; Mie scattering; dielectric metamaterials; magnetic dipole

Citation Formats

Khromova, Irina, Kužel, Petr, Brener, Igal, Reno, John L., Chung Seu, U-Chan, Elissalde, Catherine, Maglione, Mario, Mounaix, Patrick, and Mitrofanov, Oleg. Splitting of magnetic dipole modes in anisotropic TiO 2 micro-spheres: Splitting of magnetic dipole modes in anisotropic TiO 2 micro-spheres. United States: N. p., 2016. Web. doi:10.1002/lpor.201600084.
Khromova, Irina, Kužel, Petr, Brener, Igal, Reno, John L., Chung Seu, U-Chan, Elissalde, Catherine, Maglione, Mario, Mounaix, Patrick, & Mitrofanov, Oleg. Splitting of magnetic dipole modes in anisotropic TiO 2 micro-spheres: Splitting of magnetic dipole modes in anisotropic TiO 2 micro-spheres. United States. doi:10.1002/lpor.201600084.
Khromova, Irina, Kužel, Petr, Brener, Igal, Reno, John L., Chung Seu, U-Chan, Elissalde, Catherine, Maglione, Mario, Mounaix, Patrick, and Mitrofanov, Oleg. 2016. "Splitting of magnetic dipole modes in anisotropic TiO 2 micro-spheres: Splitting of magnetic dipole modes in anisotropic TiO 2 micro-spheres". United States. doi:10.1002/lpor.201600084. https://www.osti.gov/servlets/purl/1259675.
@article{osti_1259675,
title = {Splitting of magnetic dipole modes in anisotropic TiO 2 micro-spheres: Splitting of magnetic dipole modes in anisotropic TiO 2 micro-spheres},
author = {Khromova, Irina and Kužel, Petr and Brener, Igal and Reno, John L. and Chung Seu, U-Chan and Elissalde, Catherine and Maglione, Mario and Mounaix, Patrick and Mitrofanov, Oleg},
abstractNote = {Monocrystalline titanium dioxide (TiO2) micro-spheres support two orthogonal magnetic dipole modes at terahertz (THz) frequencies due to strong dielectric anisotropy. For the first time, we experimentally detected the splitting of the first Mie mode in spheres of radii inline imagem through near-field time-domain THz spectroscopy. By fitting the Fano lineshape model to the experimentally obtained spectra of the electric field detected by the sub-wavelength aperture probe, we found that the magnetic dipole resonances in TiO2 spheres have narrow linewidths of only tens of gigahertz. Lastly, anisotropic TiO2 micro-resonators can be used to enhance the interplay of magnetic and electric dipole resonances in the emerging THz all-dielectric metamaterial technology.},
doi = {10.1002/lpor.201600084},
journal = {Laser & Photonics Reviews},
number = ,
volume = ,
place = {United States},
year = 2016,
month = 6
}

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