Investigation and Control of Stress in Multilayer Optics for Next-Generation Synchrotron X-ray Applications

About the Project

The Department of Mechanical Engineering at the University of Bath is inviting applications for the following fully funded PhD project/studentship, expected to commence late September 2026.

Supervisors:

Dr Hongchang Wang & Dr A. Majhi (Diamond Light Source)

Dr Alexander J. G. Lunt & Prof Chris Bowen (University of Bath)

Project

Modern synchrotron X‑ray facilities rely on highly specialised multilayer optical components to deliver intense, coherent beams for advanced experiments across physics, materials science, engineering and biology. These multilayer systems, used in mirrors, lenses and monochromators, must maintain exceptional stability and accuracy, yet their performance is strongly affected by mechanical stress that develops during thin‑film deposition and under operating conditions. Even small stress‑driven distortions can influence beam quality, limit focusing performance, and reduce long‑term reliability on demanding beamlines.

This PhD will explore how mechanical stress evolves within multilayer X‑ray optics and how this influences the optical, spectral, and structural stability of these components. Working across Diamond Light Source and the University of Bath, the project will involve characterising stress formation during deposition, examining microstructural features that govern stress behaviour, and studying the deformation of curved or high‑precision optics under service conditions. Techniques such as curvature and X‑ray metrology, microscopy, diffraction and mechanical modelling will be used to build a detailed understanding of the factors controlling stress in these multilayer systems.

Alongside this, the project will assess strategies for producing more stable multilayer optics, including optimisation of deposition conditions and exploration of stress‑balanced material combinations. The goal is to support the development of next‑generation optical components capable of meeting the stringent requirements of modern and upgraded synchrotron beamlines.

The student will work within a world‑leading research environment, combining the advanced deposition, metrology and beamline testing facilities at Diamond Light Source with complementary materials science and thin‑film mechanics expertise at the University of Bath. This provides an excellent opportunity work alongside a dynamic, world-leading group to contribute to the design and optimisation of precision optics used by a large international research community.

Candidate Requirements

Applicants should hold, or expect to obtain, a first‑class degree (or equivalent) in Physics, Engineering, Materials Science, or a related discipline, and should have a strong interest in experimental mechanics, thin‑film systems, or X‑ray instrumentation.

Non-UK applicants must meet our English language entry requirement.

Enquiries and Applications

Informal enquiries are welcomed and should be directed to Dr Alexander Lunt - ajgl20@bath.ac.uk

Please make a formal application via the University of Bath’s online application form for a PhD in Mechanical Engineering

You should select 'Other' from the dropdown menu in the 'Funding your studies' section of the application form and must provide the supervisor's name and project title in the 'Your PhD project' section. Failure to complete these steps will result in a delay to the processing of your application and may cause you to miss the deadline.

More information about applying for a PhD at Bath may be found on our website.

Equality, Diversity and Inclusion

We value a diverse research environment and strive to be an inclusive university, where difference is celebrated and respected. We encourage applications from under-represented groups.

If you have circumstances that you feel we should be aware of that have affected your educational attainment, then please feel free to tell us about it in your application form. The best way to do this is a short paragraph at the end of your personal statement.

The Disability Service ensures that individuals with disabilities are provided the support that they need. If you state if your application that you have a disability, the Disability Service will contact you as part of this process to discuss your needs

Funding Notes

This studentship is funded by Diamond Light Source and the University of Bath, and will cover tuition fees at the Home rate and provide a annual maintenance stipend (£21,805 in 2026/27, increasing annually). This studentship is open to UK, EU, and international applicants. For Overseas fee paying students, a scholarship covering the difference between the Home and Overseas tuition fees may be available, or it may be possible for applicants to cover the difference from external sources/personal funds.