Optimal control design of matterwave interferometer laser pulses for inertial and magnetic sensing

This project is part of the EPSRC Center for Doctoral Training in Quantum Technology Engineering at the University of Southampton (https://qte.ac.uk/). In addition to the research project outlined below you will receive substantial training in scientific, technical, and commercial skills.

Project description

Inhomogeneities degrade the performance of atom interferometers used for inertial and magnetic sensing. Optimal Control allows the design of laser pulse shapes that restore interferometer fidelity. This project will extend optimal control design beyond individual pulses to entire interferometer sequences and systems, and explore curious artefacts apparent from earlier work.

Quantum inertial sensors, based upon atom interferometry, use pulses of laser light to split, steer and recombine atomic wavefunctions with precision and fidelity, promising major performance improvements for applications from navigation to geological survey. However, intensity variations across a laser beam and the motion of atoms even at microkelvin temperatures can limit sensor performance. To solve similar problems, magnetic resonance imaging uses computationally-designed phase and amplitude shaping within each pulse. We have successfully adapted these optimal control techniques to design individual ‘mirror’ and ‘beamsplitter’ pulses for atom interferometry, and have already shown major improvements, but so far we have only optimized each pulse individually. Optimization of a full interferometer sequence would be more effective and could extend to optimization of the sensor system overall.

In this project, you’ll join our computational theorists to develop optimal control for entire interferometer sequences, addressing a variety of Raman and Bragg configurations and enhancements such as large momentum transfer. You’ll then work with our experimentalists to validate them on one of our cold-atom interferometers and apply them in field trials of a prototype sensor. Finally, you’ll explore curious features seen in the optimized waveforms that suggest intuitive interpretations for computational results; and adapt your solutions for alternative applications to atom-based quantum computing. The project will help you to develop skills and expertise in quantum technologies, digital modelling, computational optimization, photonics, atomic physics, control and instrumentation.

Supervisory team: Dr Tim Freegarde, Prof Ilya Kuprov

For more information, please contact the supervisor: Dr Tim Freegarde, timf@soton.ac.uk

Entry Requirements

Undergraduate degree (at least UK 2:1 honours degree, or international equivalent).

Closing date

Applications are accepted throughout the year for a start date in September 2025. Overseas students requiring funding must apply before 31 March 2025.

Funding

Funding on a competitive basis. For UK students, tuition fees and a stipend at the UKRI rate tax-free for 4 years. EU and Horizon Europe students are eligible for scholarships. Overseas students who have secured or are seeking external funding are welcome to apply.

How To Apply

Apply online here: Select programme type “Research”, “Faculty of Engineering and Physical Sciences”, next page select “PhD Quantum Tech Eng”. In Section 2 of the application form insert the name of the supervisor.

Applications should include (further details on https://qte.ac.uk/phd-opportunities/ ):

Personal statement

Curriculum Vitae

Contacts of two referees

Degree Transcripts/Certificates to date

We are committed to promoting equality, diversity, and inclusivity and give full consideration to applicants seeking part-time study. The University of Southampton takes personal circumstances into account, has onsite childcare facilities, is committed to sustainability and has been awarded the Platinum EcoAward.