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Fabrication And Characterization Of Photonic Crystal Slow Light Waveguides And Cavities
Published on: November 30, 2012
Coupled external cavity photonic crystal enhanced fluorescence.
Anusha Pokhriyal1, Meng Lu, Chun Ge
1Department of Physics, University of Illinois, Urbana-Champaign, USA.
Journal of Biophotonics
|November 7, 2012
Summary
We developed a new method using photonic crystals and lasers to significantly boost fluorescence signals, improving biomolecule detection by 100,000 times for sensitive biological assays.
Area of Science:
- Optics and Photonics
- Biophotonics
- Materials Science
Background:
- Photonic crystals enhance fluorescence by controlling light-matter interactions.
- External cavity lasers offer tunable, narrow-bandwidth light sources.
- Improving the limit of detection is crucial for sensitive bioassays.
Purpose of the Study:
- To develop a novel approach for significantly enhancing fluorescence.
- To investigate the use of cavity-coupled photonic crystals for biomolecule detection.
- To achieve a substantial improvement in the limit of detection for fluorophore-tagged proteins.
Main Methods:
- Utilizing a photonic crystal surface as a tunable mirror for an external cavity laser.
- Exciting surface-adsorbed fluorophore-tagged biomolecules on the photonic crystal.
- Employing an automatically tuning laser cavity for optimal on-resonance coupling.
Main Results:
- Achieved a ~10x increase in the electromagnetic enhancement factor compared to standard photonic crystal enhanced fluorescence.
- Demonstrated a ~10^5x improvement in the limit of detection for a fluorophore-tagged protein.
- Observed stable and optimal coupling due to the cavity's self-tuning capability.
Conclusions:
- Cavity-coupled photonic crystals offer a fundamentally new and effective approach to enhance fluorescence.
- This method significantly reduces detection limits for optically-excited light emitters in biological assays.
- The enhanced signal and simplified alignment make this technique promising for future sensitive diagnostic tools.
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