Next-generation ultrafast science with optical attosecond solitons

About the Project

Ultrafast laser pulses allow us to follow fundamental quantum processes such as chemical reactions and electron transport at their natural timescale. To study the fastest phenomena, laser pulses with attosecond duration are required (1 as = 10-18 s), and the 2023 Nobel Prize in physics was awarded for the generation of attosecond pulses in the extreme ultraviolet (XUV) spectral region. However, XUV photon energies are far higher than the energy scale typically found in (bio)chemistry, materials science and optoelectronics, where processes are much more likely to involve photons in the optical region—the visible or ultraviolet. This leaves a blind spot in our current understanding of ultrafast dynamics in matter.

Conventional optical laser sources cannot reach attosecond duration—but this is a technological limitation, not a fundamental one. This PhD project will push far beyond the state of the art and bring attosecond time resolution to the optical domain.

The project. The PhD project will be part of the ERC Starting Grant project FASTER (https://lupo-lab.com/project/faster/). The first aim will be to develop and characterise a new source of attosecond-duration laser pulses in the optical spectral region based on tailored optical soliton dynamics in gas-filled hollow-core waveguides. The second aim is to apply this source in next-generation ultrafast spectroscopy experiments to study electronic dynamics in quantum systems such as biomolecules or strongly correlated materials. Achieving these goals will require a mixture of experimental and numerical work to design and implement advanced light sources based on hollow-core waveguides. Application experiments will involve international collaboration with groups around the world.

The project will be hosted in a newly refurbished and equipped state-of-the-art laser laboratory and supported by senior group members in addition to the PhD supervisor.

The candidate. The successful candidate will join a diverse and motivated team of PhD students and postdoctoral researchers working across a range of projects from fundamental science to industrially funded research. Candidates must have experience in experimental laboratory work and a strong grounding in the fundamentals of optics and lasers. The project will involve both experimental and computational work, so experience with programming for numerical simulations and laboratory instrument control is desirable.

The group. The project will be based in the Laboratory of Ultrafast Physics and Optics (LUPO, http://lupo-lab.com/) at Heriot-Watt University (Edinburgh, UK) under the supervision of Dr Christian Brahms (https://lupo-lab.com/author/christian-brahms/). Across four state-of-the-art ultrafast optics laboratories, the LUPO group develops and applies new laser light sources with extreme spectral and temporal properties, from compact deep-ultraviolet lasers for healthcare applications to high-power wavelength-tuneable laser pulses and extremely intense sub-cycle field transients for ultrafast science. We use a symbiotic mix of experimental work and advanced numerical simulations to push ultrafast nonlinear optics to the extreme. In close collaboration with leading research institutes and universities around the world, we use the light sources we develop to gain new insights into ultrafast dynamics in matter. The PhD project will include opportunities to join in these collaborations with other research laboratories, both in the UK and overseas.

How to apply. Interested candidates should first contact Dr Christian Brahms (c.brahms@hw.ac.uk) and arrange an informal call to discuss the project in more detail. Formal applications must be made through the Heriot-Watt on-line application system, https://www.hw.ac.uk/study/apply/uk/postgraduate.htm

Start date. The project will start in September or October 2026.

Funding

Full funding, covering fees and stipend (in line with UKRI values), is available for applicants who are UK or Irish nationals (meeting residency requirements); have settled status; have pre-settled status (meeting residency requirements); have indefinite leave to remain or enter; or are otherwise eligible for Home fee status.

Funding for excellent international applicants is available on a competitive basis. Support for visa fees and other immigration expenses may be available for a successful international applicant.