Journal article

An Optically Responsive Soft Etalon Based on Ultrathin Cellulose Hydrogels

Yue Dong, Eser Metin Akinoglu, Heyou Zhang, Fatemeh Maasoumi, Jinping Zhou, Paul Mulvaney



Stimuli-responsive optical etalons are an exciting class of next-generation sensors because they are scalable, cost-effective and offer tunability of their optical response across the entire UV–vis–NIR wavelength range. In this study, double-network cellulose hydrogels are used as a soft, responsive medium and are incorporated into Fabry–Pérot optical etalons. The thin cellulose hydrogel layer can be solution processed. The hygroscopic hydrogel undergoes both refractive index and thickness changes in response to changes in humidity. This leads to strong changes in reflection due to optical interference within the metal–insulator–metal (MIM) cavity. The response can be optimized by adjusting ..

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Awarded by ARC

Funding Acknowledgements

Y.D. designed the experiments and experimental devices, built the experiment setup, prepared the hydrogel, analyzed the etalon and co-wrote the manuscript. E.M.A. analyzed the refractive index data, and developed the EMA model and helped write the manuscript. H.Y.Z. carried out the simulations and helped write the manuscript. F.M. carried out nanofabrication of the gold layer by EBE. P.M. and J.P.Z. conceived the research, supervised the research work, and co-wrote the manuscript. This work was financially supported by the ARC through Grant CE170100026 and Chinese Scholarship Council. E.M.A. acknowledges funding by the Alexander von Humboldt Foundation through a Feodor Lynen Research Fellowship. The National Natural Science Foundation of China (51473128) supported the SEM analysis. This work was performed in part at the Melbourne Centre for Nanofabrication (MCN) in the Victorian Node of the Australian National Fabrication Facility (ANFF).