Current research interests

Nonlinear Fibre Optics

The main focus of our current research is in the area of nonlinear optics in microstructured holey fibres. We investigate their unique capability to modify the nonlinear propagation of short laser pulses with the aim to understand and exploit pulse shaping techniques in space, time, and frequency. We use computer simulations as well as approximate analytical models to study a range of applications such as supercontinuum (white light) generation, pulse compression and parametric amplification. In particular, we developed a theoretical model to describe nonlinear optical coupling between the spatial modes of multimode optical fibres. This framework is now applied for simulations of spatial-division multiplexed communication systems as well as high power lasers and amplifiers in large-mode area fibres.

High Harmonic Generation

Ultrafast laser pulses today can produce electric fields large enough to rip electrons out of the atoms of a neutral gas and then to accelerate these electrons so hard that they emit ultrashort wavelength radiation. Exploiting this effect, it will ultimately be possible to build table-top coherent XUV or soft X-ray sources that are of fundamental interest for structural imaging on the nanoscale and for ultrafast time-dependent spectroscopy. A particularly interesting geometry is to combine laser propagation, ionisation, and X-ray emission inside a single gas-filled capillary. We are developing theoretical and numerical models using the Southampton supercomputer facility to investigate the delicate, highly nonlinear interaction between pump laser, gas and X-rays to gain better understanding and, in due course, better control over such systems.

Quantum Technology

Our group is part of the National Quantum Technology Hubs (NQIT, Sensors and Metrology) which aim to transfer concepts of fundamental quantum physics, such as quantum superposition, entanglement and quantum statistics, into practical technology for real-world devices. Based on our expertise in both quantum optics and optical technology, our role in these Hubs is to design and optimise devices that operate at a single quantum level in support of experimental and fabrication groups in Southampton and at partner Universities. In particular, we investigate planar optical waveguides and Bragg gratings for single-photon logic and light delivery on chips, as well as the integration of high-finesse optical resonators and ion traps for efficient photon-matter coupling on the single-quantum level.

Our main partner groups

On all projects we collaborate closely with other research groups within the ORC, and the interaction between our modelling work and corresponding experiments is a main driving force in our research.

• Microstructured Optical Fibres
• Optical Engineering and Quantum Photonics
• Advanced Fibre Technologies and Applications
• Ultrafast Laser X-Ray Group
• Optical Biosensors and Biophotonics
• Optical Microfibre Devices and Sensors
• Optical Fibre Communications
• Distributed Optical Fibre Sensors

Publications

A list of the group’s publications can be found here https://www.orc.soton.ac.uk/people/ph8