Speaker
Description
Quantum mechanics is at its most striking when it produces states that have no classical counterpart, superpositions that refuse to behave like “either/or,” correlations that outlive distance, and measurement outcomes that cannot be explained by any classical hidden-variable story. Photons are the ideal stage for this drama: they propagate at the speed of light, preserve coherence over long distances, and can be sculpted into high-dimensional and multi-photon quantum states that are both experimentally accessible and technologically actionable. In this talk, I will trace a “discovery-to-deployment” arc for photonic quantum technologies, grounded in our experience across fundamental experiments and translational engineering. Starting from core quantum resources in light, such as superposition, interference, and entanglement, I will discuss how foundational tests of nonclassicality and measurement can be repurposed into practical capabilities within quantum communications: trustworthy entropy generation, certified key material, and protocols whose security rests on experimentally verifiable quantum behaviour rather than assumptions about computational hardness. I will highlight the role of certified quantum randomness as a central primitive for quantum communications. Nonclassical correlations enable certification of unpredictability, including device-independent approaches based on Bell nonlocality and single-system certification using temporal inequalities (Leggett–Garg). These tools illustrate a broader theme: “exotic” quantum behaviour can be engineered into an operational guarantee, and then used directly in communication and cryptographic stacks. Building on this, I will discuss progress in quantum-secure communication, including quantum key distribution and its evolution from controlled laboratory demonstrations to field-relevant implementations. I will touch on atmospheric free-space links, pointing-acquisition-tracking for moving platforms, and the pathway toward satellite-based quantum communication. Finally, I will look ahead to scalable quantum networks, where multi-node entanglement distribution, quantum repeaters, and photon–matter interfaces (quantum memories) become essential. The talk will close with lessons from translating photonic quantum prototypes into products, including reliability engineering, validation standards, and the practical constraints that determine whether an exotic quantum state remains a beautiful experiment or becomes a working technology.