32 research outputs found
Plasmonic Nano Resonators Using Asymmetric-Double-Bar Metamaterials
Get PDFTohoku University博士(工学)博士学位論文 (Thesis(doctor))要約のみthesi
Electro-optic switching in spin-coated ferroelectric mesomorphic polymer films and its analysis
Get PDFThis article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in Sadahito Uto, Hiroshi Moritake, Masanori Ozaki, Kent Skarp, and Bertil Helgee, Journal of Applied Physics 79, 4444 (1996) and may be found at https://doi.org/10.1063/1.361754.Thin films of a chiral side‐chain polymer with a ferroelectric phase were deposited on a substrate by spin coating. Electro‐optic switching in the films were observed by applying an external field using in‐plane electrodes. Characteristics of the switching are presented, together with an analysis of the switching dynamics that takes into account the inhomogenous field distribution in the active area
Impact of substrate etching on plasmonic elements and metamaterials: preventing red shift and improving refractive index sensitivity
No full textControlling bi-anisotropy in infrared metamaterials using three-dimensional split-ring-resonators for purely magnetic resonance
No full textAbstractWe propose and demonstrate the strategy to control bi-anisotropic response in three-dimensional split-ring-resonators (3D-SRRs) array for purely magnetic resonance in the mid-infrared region. By using a metal-stress-driven self-folding method, inversion symmetry along a propagation axis of 3D-SRRs was controlled. The inversion symmetry of 3D-SRRs realized non-bi-anisotropic response of a magnetic resonant mode at around 10 μm in wavelength resulting in purely magnetic resonance with high transmission of 70%. Highly transparent purely magnetic artificial elements demonstrated in this study will be a key component for functional applications using artificial magnetism at the optical frequencies.</jats:p
Bi-anisotropic Fano resonance in three-dimensional metamaterials
No full textAbstractWe experimentally investigated the bi-anisotropic properties of Fano resonance in three-dimensional (3D) metamaterials. Fano resonance in 3D metamaterials arises from the interference of in-phase and anti-phase modes that originate from mode hybridization in coupled 3D split ring resonators (SRRs) with detuned resonant wavelengths. At Fano resonance, not only permittivity and permeability but also the bi-anisotropic parameter show doubly dispersive response. Manipulation of the bi-anisotropic response at Fano resonance was demonstrated through controlling the inversion symmetry of the 3D-SRRs. Improvement of inversion symmetry due to rotation of 3D-SRRs results in enhancement of magnetic response and inhibition of electric and bi-anisotropy responses at Fano resonance. Negligible electric and bi-anisotropic responses at Fano resonance were achieved due to the small radiative nature of the anti-phase mode. This bi-anisotropic Fano metamaterials with rich and tunable bi-anisotropy will extend the capabilities of new optical phenomena and broaden the applications of bi-anisotropic metamaterials.</jats:p
Analysis of defect mode switching response in one-dimensional photonic crystal with a nematic liquid crystal defect layer
Get PDFThis article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in Ryotaro Ozakia, Hiroshi Moritake, Katsumi Yoshino, and Masanori Ozaki, J. Appl. Phys. 101, 033503 (2007) and may be found at https://doi.org/10.1063/1.2432877.We analyze the dynamic response and optical properties of a high-speed defect mode switching that is based on a tunable defect mode in a one-dimensional photonic crystal with a nematic liquid crystal defect layer. The electro-optic responses of the defect mode switching are calculated considering the director distributions in the defect layer, which are determined using continuum theory. The calculated defect mode switching exhibits a response on the order of microseconds in spite of the use of the reorientation of nematic liquid crystal molecules. From the calculation, it is found that the fast response is realized using a narrow peak shift and a fast part of the molecular reorientation. Furthermore, the dependences of the switching response are clarified on several physical parameters
Enhanced quality factor of Fano resonance in optical metamaterials by manipulating configuration of unit cells
No full textEmission wavelength tuning of fluorescence by fine structural control of optical metamaterials with Fano resonance
No full textSwitchable Unidirectional Radiation from Huygens Dipole Formed at an Exceptional Point in Non-Hermitian Plasmonic Systems
No full textNon-Hermitian (NH)
photonics has attracted considerable attention
from researchers owing to exotic properties that originate from the
parity–time (PT) phase
transition and exceptional points
(EPs). In this work, we propose and numerically demonstrate formation
of a Huygens dipole using an EP eigenstate in NH coupled plasmonic
systems. Unidirectional radiation from the artificial Huygens dipole
can be switched via the sign of a coupling constant. In our systems,
the formation of the Huygens dipole and its switchable unidirectional
radiation are manifested as long as the EP condition is fulfilled.
The presented method to control artificial electric and magnetic dipoles
based on NH systems would provide new roots to construct Huygens metasurfaces
and Huygens dipole antennas
