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In this book, we present the unique properties of Hollow-Core Photonic Crystal Fibres (HC-PCFs) for sensing applications in terms of viscosity detection and DNA sensing using a special poly(ethylene) glycol (PEGDA) hydrogel. Thus, we report the characterisation of light propagation within HC-PCFs and the development of a selective filling process with the investigation of a new viscometer device, and a new device for DNA sensing development, and also the chemical process for hydrogel growth was adapted to the fibres. By combining HC-PCFs with the hydrogel we enable 3D volumetric sample grow inside the HC-PCFs, further increasing the interaction between the sample and the optical signal. We also discussed the hydrogel influence on the guidance properties of the HC-PCF; analysed and detected immobilised labelled DNA sample within the hydrogel using the fluorescence techniques. In addition, the suspended-core optical fibres are investigated in terms of integration with the hydrogel and DNA sensing. I hope that the presented work would help working with Photonic Crystal Fibres and simplified understanding of properties of these fibres.

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My research adventure in Photonics has begun in Tyndall National Institute in Cork, Ireland, where I completed my PhD. Before this time I graduated from Wroclaw University of Technology in Poland with a degree in Applied Physics. Currently, I work in Germany on post-doctoral position in Leibniz Institute for Astrophysics.

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