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Updated: Jul 28, 2025

Novel Techniques for Observing Structural Dynamics of Photoresponsive Liquid Crystals
Published on: May 29, 2018
Photonic crystal cavity-mediated improved absorptive nonlinearity of C-4-hydroxy-3-methoxphenilcalix[4]resorcinarene
Siji Alappattu John1,2, Athulya Kadeprath Satheesan1, Simi Pushpan K3
1Laser and Nonlinear Optics Laboratory, National Institute of Technology Calicut, Calicut, Kerala, 673601, India. csk@nitc.ac.in.
Abstract:
The insertion of a nonlinear material at the photonic crystal cavity leads to a strong interaction between localized photonic modes and the introduced material's electronic state, leading to exceptionally improved nonlinear optical properties at low input power. We report the enhanced nonlinear absorption and optical limiting properties of C-4-hydroxy-3-methoxphenilcalix[4]resorcinarene (CHMPCR) in a one-dimensional polymeric photonic crystal cavity. Open aperture z-scan measurements with a nanosecond pulsed laser beam having a repetition rate of 10 Hz at 532 nm from a polymeric-based microcavity demonstrate a 4.5 times enhancement in the nonlinear absorption coefficient of CHMPCR relative to its reference film. The phenomenal increase in nonlinear response could be due to the enhanced local field-assisted effective two-photon absorption arising from the interaction of CHMPCR with intensified confined light emerging from the resonant excitation at the cavity. The low optical limiting threshold and enhanced nonlinear absorption of the CHMPCR-based photonic crystal cavity make it a promising candidate for realizing cost-effective optoelectronic devices.
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