Ultrafast laser pulses allow us to follow fundamental processes such as chemical reactions and electron transport at their natural timescale. Because optical (ultraviolet, visible or infrared) laser sources have not been able to reach the attosecond pulse duration required to investigate the fastest events, ultrafast science has moved to extreme-ultraviolet (XUV) wavelengths. However, XUV photon energies are far higher than the scale of chemically and electronically relevant valence-electron excitations, so XUV spectroscopy is at most only indirectly sensitive to some of the most important interactions. Furthermore, the low pulse energy of attosecond XUV sources has so far prevented experiments with true attosecond time resolution. In FASTER, I will push far beyond the limits of conventional laser sources and bring attosecond time resolution to the optical domain. Using advanced optical soliton dynamics in gas-filled hollow capillary fibres, I will create ultrabroadband supercontinuum probe pulses and wavelength-tuneable pump pulses from the vacuum ultraviolet (100 nm) to the near infrared (1000 nm) with both attosecond duration and sufficient pulse energy for attosecond pump-probe studies. Using the flexibility of soliton dynamics and all-optical spatio-spectral manipulation, I will tailor these pulses to specific experiments. I will then take one step further and develop two-dimensional spectroscopy with the same approach, combining ultrabroadband optical attosecond pulses with the ability to identify different excitation pathways and quantum coherences. In collaboration with expert groups, I will apply these new capabilities to some of the most challenging questions in ultrafast science and directly observe crucial valence-electron interactions with unprecedented time resolution. FASTER aims at the physical limit of optical ultrafast laser pulses and a new regime of ultrafast spectroscopy, opening up entirely new ways of observing the fastest processes in nature.

Obstacle avoidance with monocular vision is an important open problem in robotics. Measurements of optical flow (OF) carry information about potential collisions directly without the need to identify complex and abstract semantics of the video stream. However, dense OF for navigation remains a poorly explored area because, until recently, real-time dense OF estimation was simply not available. This project was aimed at harnessing the power of modern neural networks to extract collision information from dense OF of a robots video stream. A pixel-wise classifier was proposed to identify regions of high collision probability. This exploratory work discusses potential solutions to challenges specific to OF frames processing, as well as high class imbalance of the collected training data.

Humanity’s reliance on the rapid and free flow of information cannot be understated. Over the last two decades, control over the spectral, temporal, and spatial structure of light has led to a massive increase in optical data transfer rates via signal multiplexing. For example, the simultaneous encoding of information in 84,236 spatial and frequency channels was recently used for achieving a record 10 Petabit/sec data transmission rate. As quantum technologies mature, so will the needs of a quantum infrastructure that relies on the efficient and noise-robust transfer of information. Precise control over the photonic degrees of freedom (DOFs) of space, time, and frequency offer the potential to enable similar breakthroughs for the fields of quantum communication and networking, and in parallel unlock key functionalities for quantum imaging and sensing with light. PIQUaNT will develop methods for the coherent control and measurement of the high-dimensional position-momentum and time-frequency DOFs of a photon, and drive forward the creation of techniques for combating sources of noise that inhibit the long-distance transfer of multi-mode quantum information. PIQUaNT will in turn apply these techniques in demonstrations of noise-resilient, high-capacity entanglement distribution in multiple photonic DOFs over commercially available multi-mode and multi-core fibres. Through the realisation of a prototype entanglement-based high-dimensional quantum communications network, PIQUaNT will serve as a blueprint for the future development of noise-robust quantum information networks that saturate the information carrying capacity of a photon.

To provide a robust methodology for the rapid evaluation of the surface chemistry of rubber following processing to certify effective devulcanisation.

This is a PhD Project in Physics. Laser surgery using mid-infrared or ultrafast picosecond/femtosecond lasers can greatly enhance the precision and effectiveness of treatment for a wide range of diseases. Highly flexible anti-resonant microstructured fibres have now enabled endoscopic delivery within the complex structures of the body. However, in order to fully exploit this technology novel beam steering and manipulation solutions must developed, and combined with optical monitoring and sensing technologies, to fully aid and guide surgeons.