[8p-A22-1~9] 4.1 Plasmonics and Nanophotonics

16:15 〜 16:30奨励賞エントリー英語発表

[8p-A22-7] Enhanced and Directional Magnetic Dipole Emission from Er³⁺ Ions
via Toroidal Dipole Resonances in a Hexagonal Array of Si Nanodisks

〇Keisuke Moriasa¹, Daiki Yabuguchi¹, Hiroshi Sugimoto¹, Minoru Fujii¹ (1.Kobe Univ.)

キーワード：

Magnetic dipole transition、Metasurface、Mie resonance

The 1.5 μm emission of Er³⁺ ions is widely utilized in fiber lasers and amplifiers for optical telecommunications and LiDAR technologies. However, the parity-forbidden nature of the ⁴I_13/2–⁴I_15/2 transition leads to intrinsically weak light–matter interaction. Since this transition involves comparable contributions from electric dipole and magnetic dipole transitions, efficient enhancement of spontaneous emission requires control of not only the electric local density of optical states (LDOS) but also the magnetic LDOS. In this work, we develop a silicon metasurface that forms accessible magnetic hot spots via toroidal dipole resonances for enhancing the 1.5 μm emission of Er³⁺ ions.