Surface-enhanced resonance Raman scattering in optical tweezers using co-axial second harmonic generation.

Optics Express (Impact Factor: 3.53). 06/2005; 13(11):4148-53. DOI: 10.1364/OPEX.13.004148
Source: PubMed

ABSTRACT Silica particles were partially coated with silver, and a suitable chromophore, such that they could be simultaneously trapped within an optical tweezers system, and emit a surface-enhanced resonance Raman scattering (SERRS) response. A standard 1064 nm TEM00 mode laser was used to trap the bead whilst a frequency doubling crystal inserted into the beam gave several microwatts of 532 nm co-linear light to excite the SERRS emission. The con fi guration has clear applications in providing apparatus that can simultaneously manipulate a particle whilst obtaining surface sensitive sensory information.

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