1. Department of Polymer Chemistry,
Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan
2. Hitachi Research Laboratory, Hitachi Ltd., Hitachi, Ibaraki 319-1292, Japan
3. Department of Organic and Polymeric Materials, Tokyo Institute of Technology, 2-12-1-S8-36 O-okayama, Meguro-ku,
Tokyo 152-8552, Japan
4. San
Jose Research Center, Hitachi Global Storage Technologies, 3403 Yerba Buena Rd., San Jose, California 95135, United States