1,722,285 research outputs found
High-quality metamaterial dispersive grating on the facet of an optical fiber
No full textBragg gratings fabricated along the mode propagation direction in optical fibers are a powerful technology for controlling dispersion. Here we show that a dielectric metamaterial grating with sub-wavelength period fabricated in the thin layer of silicon on the fiber facet exhibits transmission resonance with quality factor exceeding 300. We demonstrate how focused ion beam patterning, commonly expected to degrade the optical performance of materials, can be exploited to create low-loss photonic nanostructures on the fiber facet. Only a few tens of nanometers in thickness, such facet gratings can be used in compact interconnects, dispersion compensation and sensing applications
Quantum Dirac phase interferometer in a plasmonic waveguide
No full textWe introduce a new quantum interference effect that can be observed in a plasmonic interferometer and is controlled by an applied magnetic field. We show that the introduced phenomenon will result in nonlinear magnetically-tuneable transmission of the interferometer even at low light intensity (few µW) and low applied magnetic field (tens of mT)
Toroidal dipolar excitation and macroscopic electromagnetic properties of metamaterials
No full textThe toroidal dipole is a peculiar electromagnetic excitation that cannot be presented in terms of standard electric and magnetic multipoles. A static toroidal dipole has been shown to lead to violation of parity in atomic spectra and many other unusual electromagnetic phenomena. The existence of electromagnetic resonances of toroidal nature was experimentally demonstrated only recently, first in the microwave metamaterials, and then at optical frequencies, where they could be important in spectroscopy analysis of a wide class of media with constituents of toroidal symmetry, such as complex organic molecules, fullerenes, bacteriophages, etc. Despite the experimental progress in studying toroidal resonances, no direct link has yet been established between microscopic toroidal excitations and macroscopic scattering characteristics of the medium. To address this essential gap in the electromagnetic theory, we have developed an analytical approach for calculating the transmissivity and reflectivity of thin slabs of materials that exhibit toroidal dipolar excitations
Resonant response of superconducting metamaterial at optical frequencies
No full textNo abstract available
Radiation-harvesting sub-THz bolometer based on resonant superconducting metamaterial
No full textWe demonstrate a sub-THz superconducting metamaterial bolometer with selective response that exploits inter-molecular electromagnetic interactions in the electrically interconnected network of superconducting resonators and superconducting phase-transition edge sensitivity of the electrical interconnect
Radiation-harvesting resonant superconducting sub-THz metamaterial bolometer
No full textWe demonstrate a sub-THz superconducting metamaterial bolometer with selective response that exploits intermolecular electromagnetic interactions in the electrically interconnected network of superconducting resonators, and superconducting phase-transition edge sensitivity of the electrical interconnect
Planar superconducting toroidal metamaterial: a source for oscillating vector-potential?
No full textWe demonstrate the first superconducting metamaterial that can exhibit a profound toroidal dipolar resonance. Quantum behaviour of the superconductor and toroidal excitation of the metamaterial are both necessary prerequisites for observing the time-dependent Aharonov-Bohm effect
Optical superconducting plasmonic metamaterial
No full textWe report on the discovery of a new type of optical plasmonic media: by observing absorption lines in a superconducting metamaterial out of Nb, we find that the Nb metamaterial shows plasmonic properties at visible wavelengths. This suggests that superconductors are a feasible platform for a new generation of plasmonic metadevices
Electromagnetic toroidal excitations in matter and free space
No full textThe toroidal dipole is a localized electromagnetic excitation, distinct from the magnetic and electric dipoles. While the electric dipole can be understood as a pair of opposite charges and the magnetic dipole as a current loop, the toroidal dipole corresponds to currents flowing on the surface of a torus. Toroidal dipoles provide physically significant contributions to the basic characteristics of matter including absorption, dispersion and optical activity. Toroidal excitations also exist in free space as spatially and temporally localized electromagnetic pulses propagating at the speed of light and interacting with matter. We review recent experimental observations of resonant toroidal dipole excitations in metamaterials and the discovery of anapoles, non-radiating current configurations involving toroidal dipoles. While certain fundamental and practical aspects of toroidal electrodynamics remain open for the moment, we envision that exploitation of toroidal excitations can have important implications for the fields of photonics, sensing, energy and information
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