Impact of the dielectric duty factor on magnetic resonance in Ag-SiO2-Ag magnetic absorber

Abstract:

Magnetic absorber in optical frequency can be fulfilled through metamaterials designing. Therein, magnetic resonance in metal-dielectric-metal metasurfaces can be manipulated conveniently, and studying the parameters impacts is the primary for applications. In this work, through changing the grating width and the thickness of silica, the magnetic resonance modes have been studied, the conditions of the phase change zone from magnetic resonance (MR) to Fabry-Pérot (FP) are given out in Ag-SiO2-Ag grating magnetic metasurfaces. The results indicate that the MR mode in metal-dielectric-metal configuration is mainly decided on the dielectric duty factor other than the sole behaviors of the thickness of dielectric and size of nanostructures. The physical mechanism is elucidated through simulated electromagnetic field distributions using finite difference time domain (FDTD) solution, and numerical analysis of effective refraction index of Ag-SiO2-Ag magnetic metasurfaces. This study may prompt development of metamaterials in basic research in condensed physics and in optical devices applications. This work has been supported by the Natural Science Foundation of Shandong Province (No.2015ZRB019MD), the National Science Fund for Young Scholars (No.11704219), the Doctoral Research Started Funding of Qufu Normal University (No.BSQD20130152), the Open Subject of Key Laboratory of Magnetism and Magnetic Materials, Ministry of Education, Lanzhou University (No.LZUMMM2019013). E-mail:[e-mail]