Faculty
Sadahiro Masuo
Major research fields
Microspectroscopy, Single Molecule Spectroscopy, Optical Functional Materials
Photosynthesis, solar cells, LEDs, and DVDs are only a few of the many phenomena and devices related to “light" in our life. In the future, light will as not only a tool but also as an energy source. To utilize light efficiently, “spectroscopy" which investigates the interaction between light and molecules (or other substances) is a very important science. In general spectroscopy, many molecules are measured as an ensemble average, where the behavior of individual molecules cannot be distinguished, and only average characteristics can be measured. In contrast, single-molecule spectroscopy (SMS) can investigate the properties of an individual molecule. SMS is a powerful technique for exploring the individual nanoscale behavior of molecules in complex local environments. Observing a single molecule removes the usual ensemble average, allowing exploration of hidden heterogeneity in complex condensed phases as well as direct observation of state changes arising from photophysics and photochemistry. In our laboratory, we use the SMS technique and other microscopy techniques to reveal photophysical and photochemical properties of nanometer-sized materials and to explore new phenomena at nanoscale. Particularly we focus on nanocrystals and nanoparticles consisting of organic molecules, conjugated polymers, semiconductor quantum dots, and plasmon of metal nanoparticles for opto-electronic applications.
Major relevant publications
- H. Naiki, S. Masuo, S. Machida, A. Itaya Single-Photon Emission Behavior of Isolated CdSe/ZnS Quantum Dots Interacting with the Localized Surface Plasmon Resonance of Silver Nanoparticles. J. Phys. Chem. C, 115, 23299-23304 (2011).
- S. Masuo, Y. Yamane, S. Machida, A. Itaya Fluorescence Behavior of Individual Charge-Transfer Complexes Revealed by Single-Molecule Fluorescence Spectroscopy: Influence of the Host Polymer Matrix. J. Photochem. Photobio. A, 227 65-70 (2012).
- S. Masuo, N. Nishi, M. Hosugi, S. Machida, A. Itaya Dependence of Single-Photon Emission from Single Conjugated Polymer Chains on their Spatial Size as Determined by Photon Correlation Measurements in Fluid Solvent. Chem. Lett., 39, 780-782 (2010).