Gas Photonics in Hollow Core Fibres 

Hollow Core Fibres guide light in a hollow space instead of solid glass, as is the case for conventional fibres. While the core and cladding holes within our fibres are hollow, they are not usually empty and the gas composition within these holes has a significant impact on the light passing through. Within our team, we investigate aspects of hollow core fibres which are related to this gas content within the fibre and exploit it for a range of applications. 

Our work spans across the full life cycle of the fibre: from investigating the evolution of chemical compounds through every step of the fibre fabrication process, through developing techniques to characterise gas pressure and composition within hollow core fibres immediately after fabrication, to measuring the impact through characterisation methods and optical performance in wide-ranging applications. For some applications, we actively control the gas content to improve the optical properties of our fibres. For applications in high sensitivity gas detection, we can load the gas sample to be tested into the fibre core to take advantage of the long gas-light interaction length within the fibre. Furthermore, we are also investigating the impact of the internal gas composition on the longer term optical and mechanical performance of our fibres, which is critical as our fibres are now being deployed in real-world projects. 

In our gas sensing activities, we take advantage of the low loss offered by hollow core fibres beyond the conventional transmission window of standard (all-solid) optical fibres. In the visible spectral region, we work on Raman-based gas sensing using hollow core fibres which are designed and fabricated specifically for this application. In the mid-infrared, we are working on broadband absorption-based gas sensing, taking advantage of the stronger absorption lines in this spectral region. 

We enjoy working with a wide range of academic and industrial partners: Heriot Watt University, Cranfield University, Cambridge University, Sheffield University, Sheffield Hallam, NPL, CERN, IS-Instruments, Jacobs and more.