Steven Kolthammer

Ian Walmsley 

Myungshik Kim

Multiphoton Quantum Interference

The importance of quantum interference in photon dynamics was revealed by the famous Hong-Ou-Mandel experiment in 1987: photons impinging on a beam splitter can exhibit non-classical bunching behaviour at the output ports. This interference is important in quantum information processing, quantum simulations, and for probing computationally complex problems such as boson sampling. I aim to investigate the interference of more particles by exploiting advanced single photon sources, integrated optical circuits, and tomographic techniques.

In a fundamental context, I have been looking at new behaviour that arises when interfering more than two photons in linear circuits. Theoretical work has led to an experiment probing interference of three photons in a fibre-based multiport device. Next steps will involve verification of the non-classical nature of this higher-order interference, and possibly scaling to higher photon numbers.

We will use the insights gained from these fundamental studies of multiphoton interference for applications in applied quantum information science. For example, generating and characterising entangled states for quantum communication such as polarisation-encoded cluster states and loss-tolerant states.