1. State Key Laboratory of Integrated OptoelectronicsCollege of Electronic Science and EngineeringJilin University 2699 Qianjin Street Changchun 130012 P. R. China
2. College of Materials Science and EngineeringJilin University 2699 Qianjin Street Changchun 130012 P. R. China
3. State Key Laboratory of Polymer Physics and ChemistryChangchun Institute of Applied ChemistryChinese Academy of Sciences Changchun 130022 P. R. China