Date: |
11 November 2019 |
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| Speaker: | Professor Harry A. Atwater Professor Hongxing Xu Professor Alex Jen |
Research in nanophotonics is yielding advances that are opening paths for conceptually new “grand challenge” photonic technologies that have not previously been achievable. I will discuss three examples. The first is realization of comprehensively tunable nanoantenna arrays, which are enable dynamic, active control of the constitutive properties of light – amplitude, phase, wavevector and polarization – opening new applications such as phased-array optical beam steering, visible light modulation for communication and thermal radiation management. A second grand challenge is bringing next-generation solar energy technology to fruition. Nanophotonic design has enabled new directions for beyond-Si photovoltaics, such as luminescent solar concentrators that can enable an efficient and stable approach to tandem-on-Si photovoltaics. Nanostructure design is also critical to generation of chemical fuels from sunlight, and recent advances in nanostructures have allowed photoelectrochemical water splitting with record efficiency. A final grand challenge for nanophotonics is design of spacecraft capable of reaching the stars beyond our solar system, since light itself is the only fuel capable of propelling spacecraft to the relativistic speeds needed to achieve interstellar travel. Recently, the Breakthough Starshot initiative has captured scientific imagination and motivated thinking about conceptual prototypes for light-driven spacecraft that could reach nearby stars within a human lifetime. I will show that this audacious concept may be closer than we imagine, if advances in nanophotonics can enable key concepts for spacecraft propulsion, instrumentation and communications.
Plasmonics is a rapidly emerging branch of photonics, which offers variable means to manipulate light using plasmon excitations on metal nanostructures. Most prominently, the huge electromagnetic enhancement of plasmonic nanocavity offers the physical basis of single-molecule SERS and many other plasmon related research fields, such as tip-enhanced spectroscopy, plasmonic antennas, plasmon hybridization, quantum plasmonics, nonlinear plasmonics, plasmonic optical forces, and plasmochemistry. In this talk, the discovery, mechanism and applications of plasmonic nanocavity are briefly introduced firstly. Then we will talk about our recent studies using plasmonic nanocavity for sub-picometer sensitivity of spatial changes, extremely high optical nonlinearity and strong coupling.
In this talk, work related to molecular engineering the shape, size, interactive forces, interfaces energy levels and Controlled Self-Assembly of organic and inorganic hybrid functional materials to result in unprecedented device performance in low power, ultrafast information processing and efficient energy generation will be discussed. The brief introduction of the CityU exciting developments in integrated photonics cluster will also be mentioned.
Professor Harry Atwater is currently Howard Hughes Professor and Professor of Applied Physics and Materials Science at the California Institute of Technology. His research interests center around two interwoven research themes: nanophotonics and plasmonics, and photovoltaics and solar energy. He is an early pioneer in surface plasmon photonics; he gave the name to the field of plasmonics in 2001. He has also created new light management principles for solar cells and high efficiency solar cell designs. He is the co-founder of the company Alta Devices, which holds the current world records for solar module efficiency and single junction cell efficiency at one Sun illumination, and which is currently taking high efficiency photovoltaics to manufacturing. His work in the solar and plasmonics field have been featured in Scientific American and in research papers in Science, Nature Materials, Nature Photonics and Advanced Materials. He also serves as Editor in Chief for the journal ACS Photonics, and is Associate Editor for the IEEE Journal of Photovoltaics, and in 2006 he founded the Gordon Research Conference on Plasmonics. He is a Fellow of the SPIE, Materials Research Society, American Physical Society and a member of the US National Academy of Engineering. Professor Atwater received his B.S., M.S. and Ph.D. degrees from MIT respectively in 1981, 1983 and 1987. He has been a member of the Caltech faculty since 1988.
Professor Hongxing Xu obtained his BS in physics from Peking University, China, in 1992 and his PhD in physics from Chalmers University of Technology, Sweden, in 2002. Then he joined Lund University, Sweden as an assistant professor. In 2005, he joined Institute of Physics, Chinese Academy of Sciences (CAS) as a professor. Then he joined Wuhan University as a professor. He is currently the Director of Center for Nanoscience and Nanotechnology, Wuhan University. He was elected as a member of CAS in 2017.
He has published more than 180 peer-reviewed papers with SCI citations >15000 and H-index >60. He was elected by Elsevier as a highly cited Chinese scholar from 2014-2018. He has given more than 70 invited presentations at international conferences, and organized more than 20 international conferences and workshops. He was the associate editor of Nanoscale, and Optics Express. He serves on the advisory board or editorial board of Nanoscale, Nanophotonics, Frontiers of Physics, etc.
He discovered the nanogap effect for huge electromagnetic enhancement, which is the physical basis of single-molecule SERS and many other plasmon-enhanced optical processes. He invented plasmonic logic gates and revealed the fundamental properties of plasmonic nanowire waveguides and networks.
Professor Alex Jen is the Provost and Chair Professor of City University of Hong Kong. He is an expert on utilizing self-assembly to create ordered organic/inorganic hybrid materials for photonics, opto-electronics, energy, and nanomedicine. He has co-authored >850 publications with >55,000 citations and a h-index of 113. He has also co-invented more than 60 patents/invention disclosures.
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Office of the Vice-President (Research)
