1. Photoelectronic Hybrid Research Center; Korea Institute of Science and Technology; Seoul 136-791 Republic of Korea
2. Department of Materials Science and Engineering; University of Washington; Seattle WA 98195 USA
3. Department of Materials Science and Engineering; Seoul National University; Seoul 151-744 Republic of Korea
4. KU-KIST Graduate School of Converging Science and Technology Korea University; Seoul 136-701 Republic of Korea
5. Department of Chemistry; University of Washington; Seattle WA 98195 USA