Enhancing fluorescence detection with a photonic crystal structure in a total-internal-reflection configuration.

In contrast to fluorescence enhancement of fluorophores embedded in a photonic crystal structure as previously reported [Appl. Phys. Lett. 75, 3605 (1999)], in this Letter we demonstrate a unique approach to forming an open microcavity using a one-dimensional photonic crystal in a total-internal-reflection geometry. This configuration opens up the possibility for enhancing fluorescence imaging and biosensing. Time-resolved fluorescence detection of fluorophores immobilized on the open cavity has been carried out. Over 20-fold fluorescence enhancement was observed.