Local plasmon sensor with gold colloid monolayers deposited upon glass substrates
| Autor: | Takayuki Okamoto, Ichirou Yamaguchi, Tetsushi Kobayashi |
|---|---|
| Rok vydání: | 2007 |
| Předmět: |
Materials science
Absorption spectroscopy business.industry digestive oral and skin physiology Surface plasmon Physics::Optics Atomic and Molecular Physics and Optics Suspension (chemistry) Condensed Matter::Soft Condensed Matter Gold Colloid Optics Colloidal gold Monolayer Surface plasmon resonance business Plasmon |
| Zdroj: | Optics letters. 25(6) |
| ISSN: | 0146-9592 |
| Popis: | A new optical sensor that uses local plasmon resonance is proposed. A peak that is due to the local plasmon resonance appears in the absorption spectrum of a gold colloid suspension in the visible region, and its height and wavelength depend on the refractive index of the suspension. These properties are used for optical sensors. We used gold colloid monolayers in which colloidal gold particles a few tens of nanometers in diameter were immobilized upon a glass slide by a functional organic coupling agent. We measured the absorption spectra of the the gold colloid monolayers, which were immersed in liquid samples or coated with thin films. We observed increases of both the resonance wavelength and the absorbance as the refractive indices of the sample liquids or the thickness of the coated films increased. The proportional constants of the resonance wavelength to the film thickness were 3.6 and 5.7 for a 13.9- and a 20.2-nm gold colloid monolayer, respectively. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|