Detection of single gold nanoparticles using spatial modulation spectroscopy implemented with a galvo-scanning mirror system

Autor: Shun S. Lo, Mary Sajini Devadas, Todd A. Major, Zhongming Li, Kuai Yu, Gregory V. Hartland, Paul Johns, Nicolas Havard
Rok vydání: 2013
Předmět:
Zdroj: Applied Optics. 52:7806
ISSN: 2155-3165
1559-128X
DOI: 10.1364/ao.52.007806
Popis: The optical extinction of single nanoparticles can be sensitively detected by spatial modulation spectroscopy (SMS), where the particle is moved in and out of a tightly focused laser beam with a piezo-device. Here we show that high sensitivity can be obtained by modulating the beam with a galvo-mirror system, rather than by moving the sample. This work demonstrates an inexpensive method for making a SMS microscope, and shows how an existing laser scanning microscope can be adapted for SMS measurements. The galvo-mirror technique also allows SMS measurements to be performed in a liquid, which is difficult to do with piezo-modulation.
Databáze: OpenAIRE