[1] Seoul Natl Univ, ReCOE, Seoul 151747, South Korea
[2] Seoul Natl Univ, Sch Phys, Seoul 151747, South Korea
[3] Changwon Natl Univ, Dept Ceram Sci & Engn, Chang Won 641773, Kyungnam, South Korea
[4] Univ Suwon, Dept Phys, Suwon 445743, Gyunggi, South Korea
[5] Soongsil Univ, Dept Phys, Seoul 156743, South Korea
[6] Seoul Natl Univ, Sch Mat Sci & Engn, Seoul 151744, South Korea
[7] Hankuk Univ Foreign Studies, Dept Phys, Yongin 449791, Gyunggi, South Korea