[1] Department of Materials Science and Engineering, Korea University, 1-5 Ka, Anam-Dong, Sungbuk-Ku, Seoul 136-701, Korea, Republic of
[2] Department of Materials Science and Engineering, Kunsan National University, San 68, Miryong-dong, Gunsan, Jeonbuk 573-701, Korea, Republic of
[3] Nano Optical Property Laboratory, Department of Physics, Kyung Hee University, 1 Hoegi-Dong, Dongdaemoon-Gu, Seoul 130-701, Korea, Republic of
[4] New Materials Evaluation Center, Korea Research Institute of Standard and Science, Deaduk Science Town, Taejeon 305-600, Korea, Republic of