Ultrashort-Pulse Optical Frequency Combs for Quantum Technologies and Sensing

Optical frequency combs are key to many Quantum Technologies: providing the 'clockwork' that stably links supremely accurate optical clocks to radio-frequency information that can be more readily exploited; and generating the ultra-stable microwave frequencies that will be required for next-generation Doppler LIDAR. However, today's optical frequency combs are generally large and lab-based, lacking the robustness to be truly mobile. This 4-year EngD project will investigate innovative new optical frequency combs that reduce size, weight and power consumption while increasing reliability and providing extremely high stability, as is required for application to next generation optical clocks and radar. The project will design, build and test optical frequency combs based upon modelocked ultrashort-pulse solid-state lasers. The project will take advantage of the Institute of Photonics at Strathclyde University and the Fraunhofer Centre for Applied Photonics' experience in diode-pumped Ti:Sapphire lasers, and push these systems further towards miniaturised and ultra-stable architectures. The project will also be supported by Caledonian Photonics Ltd, a startup company with strong links to end-users of optical frequency combs, and experience in robust solid-state laser design.

Complementing our Pathways to Impact document, here we state the expected real-world impact, which is of course the leading priority for our industrial partners. Their confidence that the proposed CDT will deliver valuable scientific, engineering and commercial impact is emphasized by their overwhelming financial support (£4.38M from industry in the form of cash contributions, and further in-kind support of £5.56M).

Here we summarize what will be the impacts expected from the proposed CDT.

(1) Impact on People
(a) Students
The CDT will have its major impact on the students themselves, by providing them with new understanding, skills and abilities (technical, business, professional), and by enhancing their employability.
(b) The UK public
The engagement planned in the CDT will educate and inform the general public about the high quality science and engineering being pursued by researchers in the CDT, and will also contribute to raising the profile of this mode of doctoral training -- particularly important since the public have limited awareness of the mechanisms through which research scientists are trained.

(2) Impact on Knowledge
New scientific knowledge and engineering know-how will be generated by the CDT. Theses, conference / journal papers and patents will be published to disseminate this knowledge.

(3) Impact on UK industry and economy
UK companies will gain a competitive advantage by using know-how and new techniques generated by CDT researchers.
Companies will also gain from improved recruitment and retention of high quality staff.
Longer term economic impacts will be felt as increased turnover and profitability for companies, and perhaps other impacts such as the generation / segmentation of new markets, and companies receiving inward investment for new products.

(4) Impact on Society
Photonic imaging, sensing and related devices and analytical techniques underpin many of products and services that UK industry markets either to consumers or to other businesses. Reskilling of the workforce with an emphasis on promoting technical leadership is central to EPSRC's Productive Nation prosperity outcome, and our CDT will achieve exactly this through its development of future industrially engaged scientists, engineers and innovators. The impact that these individuals will have on society will be manifested through their contribution to the creation of new products and services that improve the quality of life in sectors like transport, dependable energy networks, security and communications.

Greater internationalisation of the cohort of CDT researchers is expected from some of the CDT activities (e.g. international summer schools), with the potential impact of greater collaboration in the future between the next generations of UK and international researchers.