Affiliation: | a Department of Physics, Institute of Basic Science and Center for Nanotubes and Nanocomposites, Sungkyunkwan University, Suwon 440-746, Korea b Department of information and communication, Sungkyunkwan University, Suwon 440-746, Korea c Advanced Material Process of Information Technology, Sungkyunkwan University, Suwon 440-746, Korea |