Summary of Research Project Results under JSPS FY2001
"Research for the Future Program"

1.Research Institution Osaka University
2.Research Area Physical and Engineering Sciences
3.Research Field Photoscience
4.Term of Project FY 1997 〜 FY 2001
5.Project Number 97P00104
6.Title of Project Creation of Photo- and Electroactive Organic Materials and their Applications for Photonic Devices

7.Project Leader
Name Institution,Department Title of Position
Yasuhiko Shirota Osaka University, Graduate School of Engineering Professor

8.Core Members

Names Institution,Department Title of Position
Tomiki Ikeda Tokyo Institute of Technology, Research Laboratory of Resources Utilization Professor
Takatomo Sasaki Osaka University, Graduate School of Engineering Professor
Ken-ichi Machida Osaka University, Collaborative Research Center for Advanced Science and Technology Professor

9.Summary of Research Results

* Several new concepts for the molecular design of amorphous molecular materials for use in organic light-emitting diodes (OELDs) have been presented, and novel families of hole-transporting, electron-transporting, hole-blocking, and emitting amorphous molecular materials were designed and synthesized. These materials permitted the fabrication of thermally stable, high performance OLEDs. Multi-color OLEDs using novel emitting amorphous molecular materials were also developed.
* Photochromic amorphous molecular materials based on azobenzene and dithienyethene were created and their photochromic properties in the amorphous film were elucidated. Formation of surface relief grating with high diffraction efficiency and dual image formation at the same location were realized using these materials.
* A photorefractive device using an amorphous molecular material as a hole-transporting host was developed. It is shown that the device exhibits a large photorefractive effect at zero electric field in the absence of the poling process.
* Novel photochromic liquid-crystalline materials were designed and synthesized. It was found that photochemical liquid crystalline-to-isotropic phase transition can be induced by photochemical reactions of photochromic materials in nanosecond timescale and that the reorientation of liquid crystalline molecules was brought about with the molecular long axis perpendicular to the polarization direction of light. Holographic materials using these photochromic liquid-crystalline molecules were developed.
* New techniques for the growth of high quality organic single crystals were developed. High quality nonlinear optical crystals were successfully grown by using these new techniques.
* A series of silica-based hybrid materials containing rare-earth complexes were prepared by the sol-gel method. The luminescence characteristics were investigated. The hybrid materials containing europium (III) crown ether complexes have been found to exhibit good persistent spectral hole-burning characteristics that the holes persist even at room temperature.

10.Key Words

(1)Photonics、(2)Amorphous Material、(3)Single Crystal
(4)Liquid Crystal、(5)Hybrid Material