Surface-plasmon-polariton-driven narrow-linewidth magneto-optics in Ni nanodisk arrays

Nanophotonics

article

Francisco Freire-Fernández¹  Mikko Kataja¹  Sebastiaan van Dijken¹ 

[1] Department of Applied Physics, Aalto University School of Science;Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Campus de la UAB

关键词: magnetoplasmonics;    nanoparticle array;    surface plasmon polariton;    surface lattice resonance;    magneto-optical Kerr effect;   

DOI  :  10.1515/nanoph-2019-0331

学科分类：社会科学、人文和艺术（综合）

来源: De Gruyter

【 摘 要 】

The field of magnetoplasmonics exploits interactions between light and magnetic matter at the nanoscale for light manipulation and resonant magneto-optics. One of the great challenges of this field is overcoming optical losses in magnetic metals. Here, we exploit surface plasmon polaritons (SPPs) excited at the interface of an SiO 2 /Au bilayer to induce strong magneto-optical responses on the Ni nanodisks of a periodic array. Using a reference system made of Au nanodisks, we show that optical losses in Ni hardly broaden the linewidth of SPP-driven magneto-optical signals. Loss mitigation is attained because the free electrons in the Ni nanodisks are driven into forced oscillations away from their plasmon resonance. By varying the SiO 2 layer thickness and lattice constant of the Ni nanodisk array, we demonstrate tailoring of intense magneto-optical Kerr effects with a spectral linewidth down to ~25 nm. Our results provide important hints on how to circumvent optical losses and enhance magneto-optical signals via the design of off-resonance magnetoplasmonic driving mechanisms.

【 授权许可】

CC BY