- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Born-Kuhn model for magnetochiral effects
摘要： This study focuses on theoretical and numerical investigations of the magnetochiral (MCh) effect in the optical region. Electrodynamics in a medium with broken time and space inversions is described by two orthogonal coupled oscillators, in what is known as the Born-Kuhn model, subject to an external static magnetic field. Constitutive equations and the refractive index of the medium are theoretically derived. The results show that the MCh effect is induced even in the absence of an intrinsic interaction between the magneto-optical effect and the optical activity. The study also numerically investigates the electromagnetic response in a metamaterial with magnetism and chirality in the deep ultraviolet region. The results agree well with the main results of our theory. This paper paves the way to realizing MCh metamaterials in the optical region.
关键词： optical activity,magnetochiral effect,metamaterials,Born-Kuhn model,magneto-optical effect
更新于2025-09-23 15:21:01
-
Switching the Optical Chirality in Magnetoplasmonic Metasurfaces Using Applied Magnetic Fields
摘要： Chiral nanophotonic devices are promising candidates for chiral molecule sensing, polarization of diverse nanophotonics, and display technologies. Active chiral nanophotonic devices, where the optical chirality can be controlled by an external stimulus has triggered great research interest. However, efficient modulation of the optical chirality has been challenging. Here, we demonstrate switching of the extrinsic chirality by applied magnetic fields in a magnetoplasmonic metasurface device based on a magneto-optical oxide material, Ce1Y2Fe5O12 (Ce:YIG). Due to the low optical loss and strong magneto-optical effect of Ce:YIG, we experimentally demonstrated giant and continuous far-field circular dichroism (CD) modulation by applied magnetic fields from ?0.6 ± 0.2° to +1.9 ± 0.1° at 950 nm wavelength under glancing incident conditions. The far-field CD modulation is due to both magneto-optical circular dichroism and near-field modulation of the superchiral fields by applied magnetic fields. Finally, we demonstrate magnetic-field-tunable chiral imaging in millimeter-scale magnetoplasmonic metasurfaces fabricated using self-assembly.
关键词： optical chirality,magneto-optical effect,magnetoplasmonic,metasurface,circular dichroism,magnetic oxides
更新于2025-09-23 15:19:57
-
Nonreciprocal propagation in optical fibers
摘要： Nonreciprocal propagation in optical fibers presents practical interest. The present work treats the problem of nonreciprocal propagation in nonabsorbing cylindrically layered structures at axial magnetization characterized by magnetooptic electrical permittivity, ?ε, and magnetic permeability, ?μ, tensors, using transverse circularly polarized representation. The solutions to the vector Helmholtz equation are expressed analytically as functions of circular cylindrical coordinates (cid:37), ?, and z. The results are applied to a magnetooptic circular cylindrical waveguide and illustrated on fiber waveguides with an yttrium iron garnet (YIG) core and a cladding formed by gallium substituted yttrium iron garnet (GaYIG) at the optical communication wavelength of 1.55 μm. The propagation distance in the waveguide for a π/4 azimuth rotation of a transverse linearly polarized incident wave on the waveguide axis required in isolators is about 100 μm.
关键词： magneto-optical effect,Faraday effect,isolator,nonreciprocity
更新于2025-09-12 10:27:22
-
Influence of Sputtered ZnO and Al:ZnO Top Layers on Magneto-Optic Responses of Yttrium Iron Garnet Films
摘要： Zinc oxide (ZnO) is a promising material for combining with magneto-optic (MO) materials because it can propagate stable exciton-polaritons, with velocities considerably lower than that of photons in a vacuum. This study investigated the in?uence of sputtered ZnO and Al:ZnO top layers on MO responses of a bismuth-substituted yttrium iron garnet (Bi:YIG) ?lm. The ZnO top layer modulated the Faraday rotation and magnetic circular dichroism (MCD) of the Bi:YIG around the exciton resonance wavelength of ZnO at 369 nm. Furthermore, Al-substituted ZnO, which is a conductive ZnO, also changed the MO effects around the exciton resonance wavelength. These results imply that the exciton-polaritons in ZnO affect the MO interaction, because of their considerably low group velocity. The results suggest potential for controlling the MO response via excitons.
关键词： exciton,magneto-optical effect,magnetic garnet,zinc oxide,polariton
更新于2025-09-04 15:30:14