用于增强超薄磁性介电薄膜横向磁光克尔效应的超表面理论研究

Theoretical Study on Metasurfaces for Transverse Magneto-Optical Kerr Effect Enhancement of Ultra-Thin Magnetic Dielectric Films.

作者信息

Chen Jing, Wu Guohua, Gu Ping, Tang Yumei, Yang Chun, Yan Zhendong, Tang Chaojun, Liu Zhengqi, Gao Fan, Cai Pinggen

机构信息

College of Electronic and Optical Engineering, Nanjing University of Posts and Telecommunications, Nanjing 210023, China.

College of Science, Nanjing Forestry University, Nanjing 210037, China.

出版信息

Nanomaterials (Basel). 2021 Oct 25;11(11):2825. doi: 10.3390/nano11112825.

DOI:10.3390/nano11112825

PMID:34835591

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC8621794/

Abstract

We study how to enhance the transverse magneto-optical Kerr effect (TMOKE) of ultra-thin magnetic dielectric films through the excitation of strong magnetic resonances on metasurface with a metal nanowire array stacked above a metal substrate with an ultra-thin magnetic dielectric film spacer. The plasmonic hybridizations between the Au nanowires and substrate result in magnetic resonances. The periodic arrangement of the Au nanowires can excite propagating surface plasmon polaritons (SPPs) on the metal surface. When the SPPs and the magnetic resonances hybridize, they can strongly couple to form two strong magnetic resonances, which are explained by a coupled oscillator model. Importantly, benefitting from the strong magnetic resonances, we can achieve a large TMOKE signal up to 26% in the ultra-thin magnetic dielectric film with a thickness of only 30 nm, which may find potential applications in nanophotonics, magnonics, and spintronics.

摘要

我们研究如何通过在具有超薄磁性介电薄膜间隔层的金属基板上方堆叠金属纳米线阵列的超表面上激发强磁共振，来增强超薄磁性介电薄膜的横向磁光克尔效应（TMOKE）。金纳米线与基板之间的等离子体杂交会产生磁共振。金纳米线的周期性排列可以激发金属表面上的传播表面等离子体激元（SPP）。当SPP与磁共振杂交时，它们可以强烈耦合形成两个强磁共振，这可以用耦合振荡器模型来解释。重要的是，受益于强磁共振，我们可以在仅30nm厚的超薄磁性介电薄膜中实现高达26%的大TMOKE信号，这可能在纳米光子学、磁子学和自旋电子学中找到潜在应用。