2015/12/14 by Tim Raybould, T. A. Raybould, Vassili Fedotov +7 · 31 citations
Biochemistry, Genetics and Molecular Biology · Materials Science · Physics and Astronomy · #Circular polarization #Dielectric #Electromagnetic field #Electromagnetic pulse #Electromagnetic radiation #Isotropy #Magnetic and Electromagnetic Effects #Metamaterials and Metasurfaces Applications #Orbital Angular Momentum in Optics #Polarization (electrochemistry) #Refraction #Refractive index #Toroid #physics.optics
paper · pdf · open access · doi:10.1364/oe.24.003150
published in Optics Express 24(4), 3150 (Optica Publishing Group) · 11 pages, 6 figures
arxiv created 2015/12/14 · openalex publication_date 2016/02/08 · arxiv updated 2016/04/20 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
"The "focused doughnut", a single-cycle electromagnetic perturbation of toroidal topology with inseparable time and spatial dependencies propagates at the speed of light in vacuum, as was shown by Hellwarth and Nouchi in 1996. While normal incidence reflection and refraction of conventional electromagnetic pulses in isotropic media do not lead to polarization changes, "focused doughnut" pulses undergo complex field transformations owing to the toroidal field structure and the presence of longitudinal components. We also demonstrate that "focused doughnuts" can interact strongly with structured media exciting dominant dynamic toroidal dipoles in spherical dielectric particles."