By virtue of the progresses of materials sciences, nanofabrication and ultrafast laser techniques, it is now possible to explore new physics on light-matter interaction. At the moment, we are focusing on the two subjects below:

1) Photonic crystals and metamaterials:
Optical properties can be desigend by setting artificial periodic structures in materials in the scale of or much smaller than the light wavelength. We calculate, fabricate and measure unconventional electromagnetic environment to explore novel physical concepts.

2) Ultrafast phenomena in conjugated π-electron systems:
Conjugated π-electron systems have large varieties and their large and ultrafast optical nonlinearities are very important in application to optical devices. The ultrafast dynamics are investigated by using femtosecond absorption, fluorescence, and Raman spectroscopies excited by multi and tunable pump pulses. The target materials are light-harvesting complex systems in photosynthesis and single-walled carbon nanotubes encapsulating molecules.