Fluctuation in nano- and micro-imaging


  • Satoshi Kawata ⋅ JP Nanophoton Corporation, Osaka University, and RIKEN, Japan


In the advanced optical technologies, the fluctuation in the system may cause fatal errors in the measurement of extremely weak signals, degrading the accuracy and resolution of imaging and fabrication. Advanced nano-instruments such as atomic force microscopes and advanced enhanced Raman scattering microscopes, have used extremely low-noise detectors and low-noise electronic circuits. To suppress the fluctuation, experiments were made on the vibration-isolated optical tables in dark and clean rooms. Ultra-high vacuum and cryogenic technologies are also used, while samples are not alive in such an environment. In this presentation, I will talk about nano- and micro-imaging with fluctuation, where the fluctuation is rather the source of nano-imaging, but not that of the error and noise. For nano-Raman imaging of a live cell, fluctuation has been used for moving a plasmonic nanoparticle in a cell [Nano Lett. 11, 5344 (2011)]. In the method, a gold nano-particle endocytosed into a cell fluctuates randomly in the cell, and meets local molecules. A molecular map is drawn by measuring Raman scattering signals of molecules near the particle, simultaneously by detecting the trajectory of particle with a dark-field super-resolution microscope. This concept has been applied to conventional laser-scanning confocal microscopy. Rather than conventional raster scanning, a laser-beam spot fluctuates as a random walk, based on a stochastic process [J. Jpn. Soc. Precis. Eng. 87, 740 (2021)]. The method drastically reduces the experimental time, typically by a factor of five to ten. Fluctuation has been also used for the nano-fabrication of large-scale structures. If time allows, I will talk about our work on the self-fabrication of metamaterials grown in the fluctuation [APL Photonics 1, 050801 (2016)].

About the Speaker

Satoshi Kawata, Nanophoton Corporation, Osaka University, and RIKEN, Japan

Satoshi Kawata is a Professor Emeritus of Osaka University and an Honorary Scientist of RIKEN, Japan. He was a Professor of Applied Physics from 1993 to 2017 and the founding director of the Photonics Center at Osaka University from 2007 to 2015. He was also a Chief Scientist and Team Leader at the institute RIKEN from 2002 to 2015. He founded a laser-scanning Raman microscope company, Nanophoton, where he is the president and chairman. He has hosted a number of students and scientists from the Philippines in his laboratory in Osaka when he was a professor.
He is currently the President of Optica (formerly OSA), and was former President of The Japan Society of Applied Physics (JSAP), and The Spectroscopical Society of Japan.
Satoshi Kawata is one of the pioneers of near-field optics, plasmonics, nano-imaging, nano-manipulation and nano-spectroscopy. He has published more than 550 research papers in scientific journals including Nature and Science. The "8-micron bull" fabricated with his invented two-photon polymerization technology was cited in the Guinness World Records Book 2004 Edition as the smallest laser sculpture. He was awarded the Medal with Purple Ribbon from the Emperor of Japan, Leo Esaki Prize, LVMH da Vinci Excellence, Shimadzu Award and many others.

Satoshi Kawata



Article ID



Keynote Address



How to Cite

S Kawata, Fluctuation in nano- and micro-imaging, Proceedings of the Samahang Pisika ng Pilipinas 40, SPP-2022-KA-01 (2022). URL: https://proceedings.spp-online.org/article/view/SPP-2022-KA-01.