Integrated and fibre optics

Over the last 25 years, the telecommunications industry has been revolutionized thanks to the invention of the optical fibre. Optical fibres are made out of thin glass tubes that have been stretched out down to a wire no thicker than a human hair (a hundred microns). These tiny glass wires are capable of confining light and thereby transmitting information thanks to their structure. Typically, they have a radial solid core-cladding structure, where the core region has been doped with germanium to increase its refractive index. The light is confined to the core for several kilometres due to a mechanism called total internal reflection.

Although standard fibres helped us to achieve so many advances in a very wide range of disciplines, they have their limits. For example, in telecommunications, we are reaching a capacity crunch as we have reached the maximum amount of data that can be transmitted simultaneously through a standard telecom optical fibre. Here in Bath, we are investigating a new type of fibres called hollow-core fibres. In contrast to standard fibres, in hollow-core fibres, the light is guided in the air. This is achieved due to the structure of the fibre which consists of a ring of silica capillaries around the hollow core. The thin walls of the capillaries act as resonators, confining the light in the hollow core over a range of wavelengths. These fibres open up an array of new applications in quantum technology, high power delivery, medical imaging, deep-UV and far-IR guidance, as well as light-matter interactions.

Selected publications

Machnev, et al., Photonics Research, 9(8), 1462-1469 (2021)

Yerolatsitis, et al., Journal of Lightwave Technology, 38(18), 5157-5162 (2020)

Allen, et al., Physical Review Applied, 12, 044073 (2019)

Funding

P. J. Mosley, J. C. Knight & K. R. Rusimova, BT, £317k (2022-2023)

P. J. Mosley & K. R. Rusimova, Innovate UK, £200k (2022-2023)

P. J. Mosley, T. Birks & K. R. Rusimova, Innovate UK, £520k (2022-2025)