Research

Nanoscale Heat Transport

We use optical pump-probe techniques to explore heat transport over sub-micron length scales and at interfaces between dissimilar materials. The work aims to understand what guides energy transfer, particularly at metal-dielectric interfaces and in new nanoscale materials such as graphene, in order to guide the development of useful electronic devices that can withstand the heat dissipated while in operation. Currently we exploit Frequency-Domain Thermo-Reflectance (FDTR) and Time-Domain Thermo-Reflectance (TDTR), incorporating techniques such as frequency mixing or beam offsetting the pump and probe beams to explore quasi-ballistic and anisotropic heat transfer regimes.

Fusion Fuel Cycle Technologies

Fusion power generation depends on a complex ecosystem of technologies. We specialize in the fusion fuel cycle, in particular we are developing technologies for exhaust gas pumping, separation of contaminants from unburnt fuel, hydrogen and helium isotope separation, duterium and tritium enrichment. We are currently reseaching means to efficiently separate hydrogen isotopes directly in water as means to economically enrich deuterium and tritium content from trace levels, for applications in deuterium production and tritium waste recovery.

Magnetization Dynamics

Future data storage technologies aim to continue exploiting magnetic materials as storage medium. Whether for Heat-Assisted Magnetic Recording (HAMR), All-Optical magnetization Switching (AOS) or Magnetic Random Access Memories (MRAM), detailed knowledge of the dynamics of the magnetic spins is necessary to engineer useful data storage systems and predict how well they scale as the technology is advanced and bit size is reduced. The dynamic behavior of magnetic spins is well known at low temperatures down to picosecond time scales. However, as the electron temperature approaches the Curie point, the magnetization dynamics becomes richer, can't be described within the Landau-Lifshitz-Gilbert framework and longer-lived phenomena ensue. We explore the magnetization dynamics near these thermal limits with the aim of improving predictive models. To this end, our facilities allow us to study magnetic materials over variable heating/cooling time scales, and with arbitrary magnetic field orientation.

Collaborations

We frequently collaborate with the following groups: