[16a-B4-1~9] 4.1 Plasmonics and Nanophotonics

10:45 AM - 11:00 AM JST(1:45 AM - 2:00 AM UTC)English Presentation

[16a-B4-5] Broadband Absorption Spectroscopy via Plasmon Nanofocusing

〇(M2)Haruki Kidoguchi¹, Prabhat Verma¹, Takayuki Umakoshi¹ (1.Osaka Univ.)

Keywords:

plasmon,absorption spectroscopy,near-field light

Plasmon nanofocusing is a phenomenon that can generate a strong nanoscale light source over a broad wavelength range through plasmon propagation on a tapered metallic structure. It holds great potential to realize highly sensitive broadband absorption sensing, which is not possible with typical techniques based on plasmon resonance with a narrow wavelength range. In this research, we demonstrate the broadband absorption sensor based on plasmon nanofocusing. I fabricated a two-dimensional metal tapered structure to excite plasmon nanofocusing and aquired absorbance spectra of three different molecules, which have different absorption peaks spanning from 500 to 850 nm over a broad wavelength range. The results were in good agreement with those obtained by an ordinary UV-Vis spectrometer. Also, we confirmed that our method has a linearity despite the limited detection sensitivity due to the mechanical drift of optical components at this moment.