Article

Enhanced two-photon fluorescence excitation by resonant grating waveguide structures

ICFO--Insitut de Ciències Fotòniques and Universitat Politècnica de Catalunya, 08034 Barcelona, Spain.
Optics Letters (Impact Factor: 3.18). 10/2004; 29(17):1989-91. DOI: 10.1364/OL.29.001989
Source: PubMed

ABSTRACT Enhanced two-photon fluorescence (TPF) spectroscopy with novel high-finesse resonant polymeric grating waveguide structures (GWSs) is presented. Under resonant conditions the field enhancement at the surface of a GWS can be exploited for TPF spectroscopy without the need for highly focused laser excitation light. We compare the TPF obtained by placing a drop of tetramethylrhodamine (TMR) on top of a GWS with that obtained with TMR on top of a glass substrate. Our procedure and results indicate that the detection of TPF can be improved by a factor of 10 with resonant GWSs.

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