title: Magnetic plasmonic Fano resonance at optical frequency.
abstract: Plasmonic Fano resonances are typically understood and investigated assuming electrical mode hybridization. Here we demonstrate that a purely magnetic plasmon Fano resonance can be realized at optical frequency with Au split ring hexamer nanostructure excited by an azimuthally polarized incident light. Collective magnetic plasmon modes induced by the circular electric field within the hexamer and each of the split ring can be controlled and effectively hybridized by designing the size and orientation of each ring unit. With simulated results reproducing the experiment, our suggested configuration with narrow line-shape magnetic Fano resonance has significant potential applications in low-loss sensing and may serves as suitable elementary building blocks for optical metamaterials.
authors.affiliation: School of Physics, State Key Lab for Mesoscopic Physics, Peking University, Beijing, 100871, China.
authors.forename: Yanjun
authors.initials: Y
authors.lastname: Bao
authors.forename: Zhijian
authors.initials: Z
authors.lastname: Hu
authors.forename: Ziwei
authors.initials: Z
authors.lastname: Li
authors.forename: Xing
authors.initials: X
authors.lastname: Zhu
authors.forename: Zheyu
authors.initials: Z
authors.lastname: Fang
keywords: Fano resonance; magnetic modes; nanostructures; plasmonics; polarized light; surface plasmons