​Sub-atomic-scale Plasmonic Dynamics are Measured at Picometre Precision by MAE-led International Research Team 

An international research team led by MAE Nanyang Assistant Professor & NRF Fellow KIM Young-Jin and Pusan National University and POSTECH, Korea has developed a technology which measures sub-atomic-scale small thermos-dynamic motions at picometre precision (1×10^-12 m), 240 times more precise and 1000 times faster than current plasmonic rulers. Their research paves the way to real-time monitoring of nanoscopic sample dynamics in physical, chemical, and biological sciences.

The Frequency-comb-referenced (FCR) differential plasmonic phase spectroscopy developed by the international research team provides two orders of magnitude higher measurement resolution which could enable sub-molecular bio-chemical sensing, and three orders of magnitude faster detection speed which enables real-time monitoring of dynamic chemical reactions, such as DNA hybridization or formation of molecular bonding. In addition, sub-nm gap plasmonic structures can be precisely characterized for understanding the tunnelling effect between the gap and local field distribution for strong field physics.

The team has demonstrated that FCR phase spectroscopy can provide high-speed, high-resolution, and high-linearity to plasmonic rulers, with direct traceability to a time standard. The technology successfully measured the 1.94 Å dynamic motion of a pair of nanoholes with a resolution of 1.67 pm. The interaction through the propagation of the plasmonic field is enhanced by a factor of 155 compared to the physical sample length.

The team's findings have been published recently in Nature Physics.