The detection and monitoring of substances at range is extremely important to several industrial production and safety processes. This programme will be focused on remote gas sensing in air using Raman scattering for safety in nuclear and hydrogen fuel industries.

Raman scattering signal, albeit weak, provides a unique signature of chemical substance, making it an excellent tool for substance identification.

The strength of the Raman signal increases with a shorter excitation wavelength. Therefore, combining UV Raman spectroscopy with single photon detectors creates an excellent technology for remote gas monitoring applications. The project will develop a novel remote gas sensing system platform using state-of-the-art technologies in light sources, spectral analysis, and single-photon detectors.

The development will include optimisation of operational wavelength range to maximise technology sensitivity, study of Raman spectra of different molecules in a desired spectral range and designing a suitable spectrometer system. As a result, deployable prototypes will be tested for the realistic end-user scenario. Such an endeavour would represent a highly timely, novel and disruptive achievement. Our use of single-photon detectors also plays an essential role in the UK Quantum Technologies agenda, and will result in a timely and highly innovative early industrial application of these devices.

Molecular LIDAR system

We will develop a molecular LIDAR system that projects a pulse of excitation light into the field of view and then collects the few back-scattered Raman photons. The photon time-of-flight tells us the position of the cloud; the ‘colour’ of the Rama photon tells us the composition of the cloud; and the number of Raman photons tells us the concentration.

This technique requires careful timing of the outgoing pulse and detecting the returning photons.

We, therefore, make extensive use of time-correlated, single-photon detection.

To date, we have used commercial instrumentation, but the considerable expertise of the academic partner (Dr David Li) means that bespoke FPGA hardware (Wang et al., IEEE Trans. Ind. Electron. 2024 10.1109/TIE.2024.3370941; Wang et al., IEEE Trans. Ind. Electron. 70, 4256-4266, 2023; Xie et al., IEEE Trans. Ind. Electron. 69, 4264-4274, 2022) can be developed for more compact, cost-competitive embodiments. The student will be involved in the development of all subsystems of the instrument – excitation source selection and procurement; beam manipulation and projection; optical design of the collection telescope; wavelength sorting of the collected Raman photons; control instrumentation and embedded software design.

Further information

Industrial partner

The candidate will be part of a highly motivated team within the Fraunhofer Centre for Applied Photonics (CAP). Fraunhofer CAP is a world-leading centre in the field of applied photonics in central Glasgow. Fraunhofer CAP engages in industry-driven research and development (R&D) activities that benefit the UK economy and its citizens and enjoy excellent links with various industrial partners. The candidate will be able to experience translating their technology from the research laboratory to end-use.

Fraunhofer CAP is a professional R&D organisation and, as such, maintain core hours of operation. However, we are flexible in our approach and welcome such discussions.

Diversity Management at Fraunhofer