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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

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.
 [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:
Report Number(s):
Journal ID: ISSN 1863-8880; 637692
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Laser & Photonics Reviews
Additional Journal Information:
Journal Name: Laser & Photonics Reviews; Journal ID: ISSN 1863-8880
Research Org:
Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Sponsoring Org:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
Country of Publication:
United States
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; Terahertz spectroscopy; Mie scattering; dielectric metamaterials; magnetic dipole
OSTI Identifier: