Softmatter Physics

Staff Professor Jun Yamamoto
Associate Professor Yoichi Takanishi
Assistant Professor Taiki Yanagishima

Soft matter is a generic name of substances such as liquid crystal, polymer, gel, colloid and surfactant etc. In soft matter, heterogeneous molecules spontaneously and hierarchically form ordered structures. In our surroundings, there are plenty of soft matter, from liquid crystal displays to biological structures. In our laboratory, we use various advanced methods such as polarized, fluorescence and phase contrast microscope, X-ray diffractometer, laser, and synchrotron radiation to measure the structure of substances and to elucidate its physical origin. Furthermore, using dynamic light scattering and viscoelastic spectroscopy, we also measure dynamics and fluctuation of substances and molecular transport phenomena to understand them universally.

Frustration in soft matter composite system

Dynamic coupling of dynamics and nano-structure formation
In liquid crystals doped with impurities such as heterogeneous molecules, polymers, and particles, frustration between liquid crystal order and impurities occurs, and creates new phases, nano-structures, and new dynamics coupled with such structures appears. In our laboratory, we have found various new complex liquid crystalline phases like a mysterious optically isotropic ordered phase. In addition, using broadband and highly sensitive spectroscopic experimental equipments, we study the phase transition, nanostructure and the characteristic fluctuation of these novel phases in various spacial and time scales.

Molecular manipulation and photonic structure

We have devised the principle of nonel molecular manipulation driven by spatial variation of liquid crystalline order, and succeeded in demonstrating molecular manipulator prototype using photo-excited isomerization of azo dyes. We develop this system, and study the tunable photonic structure generation using an improved molecular manipulator with laser interference fringes.

Microsphere complex including liquid crystals

DDS nano-micelles and microsphere laser of nano-emulsion
We have succeeded in confining liquid crystals into microspheres using specific polymers as a surfactant and dispersing these spheres into water. In this almost transparent system, we confirmed the isotropic liquid-liquid crystal phase transition within the microspheres. Furthermore, we are trying to control of confinement and release of substances and electromagnetic waves. Such novel nano-composites are highly useful and valued as drug delivery systems (DDS) and microsphere laser emitting the light in all direction.