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Fabrication And Characterization Of Photonic Crystal Slow Light Waveguides And Cavities
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Light waveguiding in bioinspired peptide nanostructures.
Boris Apter1, Nadezda Lapshina2, Amir Handelman1
1Faculty of Engineering, Holon Institute of Technology, Holon, Israel.
Summary
Bioinspired peptide nanostructures exhibit dual optical waveguiding modes. Thermal refolding induces a switch from passive to active fluorescent waveguiding, enabling advanced photobiomedicine applications.
Area of Science:
- Biophotonics
- Materials Science
- Nanotechnology
Background:
- Peptide nanostructures possess unique optical properties influenced by secondary structure.
- Thermal refolding alters peptide conformation, impacting optical absorption and fluorescence.
Purpose of the Study:
- To investigate the structure-sensitive, bimodal nature of optical waveguiding in peptide nanoensembles.
- To differentiate between passive and active waveguiding mechanisms in bioinspired materials.
Main Methods:
- Analysis of thermally mediated conformational transitions (α-helical to β-sheet) in peptide nanostructures.
- Characterization of optical absorption and fluorescence spectra.
- Experimental observation and analysis of optical waveguiding phenomena.
Main Results:
- A conformational transition from α-helical to β-sheet structures was induced.
- Passive waveguiding via classical optics was observed in the α-helical state.
- Active fluorescent waveguiding, attributed to exciton-polariton propagation, was revealed in the β-sheet state, observable below the diffraction limit.
Conclusions:
- Optical waveguiding in peptide nanoensembles is a bimodal phenomenon dependent on secondary structure.
- Distinct physical mechanisms govern passive and active waveguiding, with different material requirements.
- The biocompatibility and biodegradability of these peptide materials suggest significant potential in photobiomedicine for bioimaging, diagnostics, and optogenetics.