[15a-2G-1~11] 3.12 Nanoscale optical science and near-field optics

△ [15a-2G-10] High-Quality Resonance in Optical Metamaterials Composed of Symmetric Structures

〇(DC)Yuto Moritake¹, Yoshiaki Kanamori¹, Kazuhiro Hane¹ (1.Tohoku Univ.)

Keywords:metamaterials,plasmonics,Fano resonance

We demonstrated Fano resonance with a high quality factor in optical metamaterials composed of symmetric structures. Although asymmetric structures are frequently used to obtain Fano resonance in metamaterials, it is known that combination of symmetric structures can also show Fano resonance. Symmetric double bar (DB) structures with two different sizes were introduced in optical metamaterials and realized excitation of a dark mode with small dipole moment. Measured optical spectra of fabricated metamaterials showed sharp Fano resonance at a wavelength of around 1600 nm. The Fano resonance resulted from interference between a dipole mode and a dark mode in which dipoles in two DBs oscillated in opposite phase.