We are an experimental quantum photonics research group in the Heriot-Watt University department of Physics, located in the beautiful city of Edinburgh, Scotland.
A brief summary of our group’s research interests is given below.
High-Dimensional Quantum Information
In the past, the field of quantum information has primarily focused on two-level quantum systems, or qubits. However, quantum states in nature can be significantly more complex, consisting of many more levels than just two. In our group, we study such high-dimensional systems both from a theoretical and experimental perspective, and apply them for developing exciting new applications in quantum information, significantly beyond the binary (qubit) regime. Our experimental efforts focus on using the spatial and temporal structure of light as a high-dimensional quantum playground for exploring a plethora of new possibilities—from encoding vast amounts of information on a single photon, to the teleportation of a complex multi-level quantum system.
Complex Quantum Photonics
In recent years, scientists have gained exquisite control over light propagation through complex scattering media such as a layer of paint or a multi-mode fibre, leading to exciting new possibilities for biomedical imaging. We are harnessing this transformative potential of complex media for quantum information science by developing them as a naturally high-dimensional platform for controlling and manipulating complex multi-mode quantum states of light. Our work focuses on the precise control of quantum state propagation through multi-mode waveguides, with applications in quantum technologies based on communication, imaging, and computation.
The entanglement of an increasingly large number of two-level systems (qubits) has been demonstrated in physical systems as diverse as ions and superconducting circuits. However, photons are currently the only system that allow us to push multi-partite entanglement in a different direction, i.e. the entanglement of multi-level quantum systems or “qudits.” Such entangled states can exhibit beautiful asymmetric structures and enable new tests of local-realism not possible with qubits. We are developing new methods to create and certify such complex multipartite entanglement with the temporal and spatial photonic degrees of freedom.
Noise-Resistant Quantum Communication
In a world where we are increasingly reliant on digital means of communication, information security plays an important role. Entanglement allows us to communicate with unconditional security against even the most sophisticated types of hacking attacks. However, the distribution of entangled states of light over large, real-world distances and through noisy environments poses a key challenge. In addition to an increased information capacity, high-dimensional quantum states offer a natural resistance to noise, allowing us to surpass some of the limitations of qubit-based networks. We are developing noise-robust quantum communication methods that use temporal and spatial encoding to achieve record information capacities and operate in real-world environments, such as existing telecom networks.
Fundamental Tests of Quantum Mechanics
Capturing the imagination of scientists and philosophers alike, entanglement is one of the most counterintuitive phenomena in Quantum Mechanics. Besides being a workhorse of quantum technologies, entanglement has shaken our very understanding of reality via experimental tests of the concept of Local Realism. While such tests have traditionally been theorised and performed with qubits, the emergence of the field of high-dimensional quantum information presents new possibilities in this direction. We are interested in exploring new fundamental studies of quantum mechanics enabled by high-dimensional quantum systems, and testing them in the lab with the complex quantum photonic systems discussed above.
European Research Council (ERC) Starting Grant
UK Space Agency
EPSRC Early Career Fellowship
QuantERA ERA-NET Co-fund (European Commission and the FWF)