High-performance ultrafast fibre lasers for biomedical applications

About the Project

Supervisory Team: Dr. Lin Xu and Prof. Sumeet Mahajan

This project develops high-performance ultrafast fibre lasers using advanced mode-locking, pulse compression, and power scaling techniques. Targeting applications in multiphoton microscopy, it combines cutting-edge laser physics with biological imaging.

The work offers hands-on experience in experiments and simulations, with strong academic and industrial collaboration in a rapidly advancing research field.

Ultrafast lasers delivering femtosecond pulses are transforming a wide range of scientific and industrial fields: from physics and chemistry to biology, medicine, and materials processing. A key enabler of this transformation is the shift from bulky, high-maintenance Ti:sapphire lasers to more compact, efficient, and cost-effective fibre lasers.

Ultrafast fibre lasers offer superior performance, low maintenance, and high flexibility, making them a rapidly advancing area of laser science. This PhD project focuses on the development of advanced mode-locking techniques to realise high-performance ultrafast fibre lasers.

You will explore novel methods for pulse compression and power scaling, targeting the generation of high-peak-power femtosecond pulses at 1 µm and 2 µm using ytterbium- and thulium-doped fibres. These sources will be applied in multiphoton microscopy for high-resolution biological tissue imaging.

The project is supported by a £5M EPSRC Programme Grant (EP/T020997/1) and a £1.6M EPSRC Prosperity Partnership Grant (EP/V038036/1), offering a unique opportunity to contribute to cutting-edge laser development and its application in nonlinear bioimaging.

You will gain valuable skills in experimental optics and numerical simulation, while working closely with experts in biophotonics and industry collaborators. The scope of the research can be tailored to align with your interests and background.

This is an excellent opportunity to launch a successful research career in one of the fastest-growing areas of photonics.

Entry Requirements:

A UK 2:1 honours degree, or its international equivalent in one of the following:

• physics
• photonics

or a closely related discipline.

Fees & Funding:

Full scholarships include tuition fees, a stipend at the UKRI rate plus 10% ORC enhancement tax-free per annum for up to 3.5 years (totalling £22,858 for 2025/26, rising annually) and a budget of £4200 for things like conference travel.

UK, EU and Horizon Europe students are eligible for scholarships.

The China Scholarship Council (CSC) students are eligible for fee waivers.

Funding for other international applicants is very limited and highly competitive.

Overseas students who have secured or are seeking external funding are welcome to apply.

How to Apply:

Apply now

You need to:

• choose programme type (Research), 2026/27, Faculty of Engineering and Physical Sciences
• select Full time or Part time
• search for programme PhD ORC (7097)
• add name of the supervisor in section 2 of the application

Applications should include:

• your CV (resumé)
• 2 academic references
• degree transcripts and certificates to date
• English language qualification (if applicable)

The School of Optoelectronics (ORC) is committed to promoting equality, diversity inclusivity as demonstrated by our Athena SWAN award. We welcome all applicants regardless of their gender, ethnicity, disability, sexual orientation or age, and will give full consideration to applicants seeking flexible working patterns and those who have taken a career break. The University has a generous maternity policy, onsite childcare facilities, and offers a range of benefits to help ensure employees’ well-being and work-life balance. The University of Southampton is committed to sustainability and has been awarded the Platinum EcoAward.