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arXiv · 2503.15651

Thermal Shrinkage-Induced Modifications in Photonic Band Gaps of Two-Photon Polymerized Bragg Reflectors

Yu-Shao Jacky Chen·Mike P. C. Taverne·Kevin Chung-Che Huang·Ying-Lung Daniel Ho·John G. Rarity
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Abstract

One-dimensional (1D) polymer-based photonic crystals (PhCs) in the $1.55~\mu{}m$ wavelength range can be easily created using a two-photon direct laser writing system. To achieve shorter period structures, we report the use of thermal shrinkage of two-photon polymerized structures, at elevated temperatures, to eliminate unpolymerised material, leading to the uniform shrinkage of the distributed Bragg reflector (DBR) structures by a ratio of $\sim$ 2.5 to 5. Our Finite Difference Time Domain (FDTD) simulation and the angle-resolved light scattering characterization technique using Fourier image spectroscopy (FIS) measurements show that the low order photonic bandgaps of DBRs blue-shift across the NIR-visible region (850 to 400 nm) as the shrinkage increases.

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Yu-Shao Jacky Chen, Mike P. C. Taverne, Kevin Chung-Che Huang, Ying-Lung Daniel Ho, John G. Rarity. 2025-03-19. Thermal Shrinkage-Induced Modifications in Photonic Band Gaps of Two-Photon Polymerized Bragg Reflectors. https://doi.org/10.1002/adpr.202500077

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