RESEARCH FIELD

Quantum Optics

Quantum optics studies the interaction of light and matter at the quantum level, where photons exhibit non-classical correlations that enable transformative applications in quantum communication, quantum computing, and quantum sensing. The field encompasses cavity quantum electrodynamics where single atoms strongly coupled to optical or microwave cavities permit single-photon non-linearity; the generation and detection of entangled photon pairs via spontaneous parametric downconversion; continuous-variable quantum optics using squeezed states of light for Heisenberg-limited measurements; single-photon sources including quantum dots and defect centres in diamond for quantum networks; and quantum key distribution protocols securing communication channels with information-theoretic guarantees. Quantum optics experiments have demonstrated fundamental tests of quantum mechanics including Bell inequality violations, quantum teleportation, and loophole-free Bell tests. These underpin emerging quantum communication networks and photonic quantum computing architectures. Funding comes from quantum technology programmes including the EU Quantum Flagship, US National Quantum Initiative, and UK National Quantum Technologies Programme.