Laser observation and control of superfluid physics

Project level: PhD

Superfluid helium is a strongly interacting quantum fluid with counter-intuitive behaviour such as flow without dissipation, the ability to flow up walls and quantised angular momentum. It has many potential applications in quantum-enhanced sensing and quantum computing. Most recently, theoretical research on the topological properties of two dimensional superfluid helium has been awarded the 2016 Nobel Prize in Physics. In our laboratory, we have developed new laser-based on-chip nanophotonic techniques to observe and control two dimensional superfluid helium at microscale, including the first demonstration of laser cooling of any liquid and the first real-time observation of thermally driven dynamics of phonons within the fluid. This combination of superfluid physics with nanophotonics provides a previously unprecedented ability to engineer the behaviour of superfluid helium, opening up the prospect of a range of new applications in quantum technology. Furthermore, it provides the possibility to directly confirm, for the first time, the existence quantised vortices in two dimensional helium – the basis of the 2016 Nobel Prize – and to experimentally explore the fundamental quantum hydrodynamics of a strongly interacting quantum fluid. PhD projects are available in both areas. Experience/interest in laser-based measurements, micro-/nanofabrication/cryogenics, cavity optomechanics and/or quantum condensed matter physics would be an advantage.