Manipulation of Giant Faraday Rotation in Graphene Metasurfaces

Faraday rotation is a fundamental magneto-optical phenomenon used in various optical control and magnetic field sensing techniques. Recently, it was shown that a giant Faraday rotation can be achieved in the low-THz regime by a single monoatomic graphene layer. Here, we demonstrate that this exceptional property can be manipulated through adequate nano-patterning, notably achieving giant rotation up to 6THz with features no smaller than 100nm. The effect of the periodic patterning on the Faraday rotation is predicted by a simple physical model, which is then verified and refined through accurate full-wave simulations.Comment: 4 pages, 5 figures, submitted to Applied Physics Letter

Unveiling Magnetic Dipole Radiation in Phase-Reversal Leaky-Wave Antennas

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Seismic Waveguide of Metamaterials

We have developed a new method of an earthquake-resistant design to support conventional aseismic designs using acoustic metamaterials. We suggest a simple and practical method to reduce the amplitude of a seismic wave exponentially. Our device is an attenuator of a seismic wave. Constructing a cylindrical shell-type waveguide that creates a stop-band for the seismic wave, we convert the wave into an evanescent wave for some frequency range without touching the building we want to protect.Comment: 4 pages, 4 figure

Reverse Doppler Effect of Sound

We report observation of reverse Doppler effect in a double negative acoustic metamaterial. The metamaterial exhibited negative phase velocity and positive group velocity. The dispersion relation is such that the wavelength corresponding to higher frequency is longer. We observed that the frequency was down-shifted for the approaching source, and up-shifted when the source receded

L'utilisation des SIG dans la modélisation en hydrologie de surface

From a methodological point of view, hydrological modelling appears to offer a great potential for spatial analysis. However among classes of models, only physical models consider the spatial dimension as a variable. The topography and the land cover are the two major spatial components involved in that type of models. The production of a relevant DTM requires the use of iterative interpolation procedures. Land cover and its changes can be monitored and entered into modelling from remote sensing images through a normalized Vegetation index. The GIS approach can be integrated at different levels within hydrological modelling, with object oriented GIS seen as the highest level

Observation of the Zero Doppler Effect

This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material.National Basic Research Program (973) of China (No. 2011CB922001), and National Natural Science Foundation of China (No. 11234010)