[6a-A410-1~9] 4.1 Plasmonics

△ [6a-A410-3] Metallic tips for efficient plasmon nanofocusing and advanced optical nano-imaging

〇Takayuki Umakoshi¹, Yuika Saito², Prabhat Verma¹ (1.Dept. of Applied Physics, Osaka Univ., 2.Dept. of Chemistry, Gakushuin Univ.)

Keywords:plasmon, plasmon nanofocusing, scanning probe microscopy

Plasmon nanofocusing, energy compression of propagating plasmons on a tapered metallic tip, is a promising tool for near-field scanning optical microscopy due to its unique properties such as background suppression and broadband property. Although applications of plasmon nanofocusing has been still limited so far, it would make the plasmon-nanofocusing-based techniques more reliable and practical if an efficient fabrication method of metallic tips is established.
In this work, we introduce a tip fabrication for efficient plasmon nanofocusing, in which we achieved 100% reproducibility of plasmon nanofocusing in more than 20 fabricated tips through precise optimizations of fabrication processes. Such an efficient plasmon nanofocusing easily led us to perform optical nano-imaging and even a brand-new nano-imaging technique, scattering spectral nano-imaging via broadband plasmon nanofocusing.