Title: Information processing with exciton-polaritons

Speaker: Timothy C H Liew, Nanyang Technological University

Time：2025-06-23 10:30

Venue: Physics Building W105

Abstract: Exciton-polaritons are well-known for hybridizing light and electronic states of matter. They should lead to optoelectronic applications. This talk will discuss concepts for polariton information processing devices, including circuits, automata, neural networks, and simulators. We need to respect that, as a photonic system we can not have the same energy efficiency as existing electronic systems. While polaritonics is greatly advancing from cryogenically cooled samples to materials capable of room temperature operation, which corresponds to orders of magnitude improvement in energy efficiency, the wavelength of a polariton greatly exceeds that of an electron giving rise to relatively large area footprints. Nevertheless, reproducing electronic architectures allows us to learn more about what polaritons can do. Such advancements could put us in a better position to harness the potential quantum nature of polaritons, which may be where the true advantages of polaritonics lie.

Bio: Timothy C H Liew works on the theory of exciton-polaritons. He has predicted fundamental effects such as the unconventional blockade, polariton topological insulators, topological spin Hall effect, and the superbunching of bosonic cascades (all of which were confirmed experimentally). His dream is that exciton-polaritons will find applications in optoelectronic information processing. He has contributed schemes of such devices. Proof-of-principle experiments have been promising for classical switches and neural networks. He is especially interested in how exciton-polaritons can exploit quantum advantages.