1. Contribution from the National Creative Research Initiative Center for Oxide Nanocrystalline Materials, and School of Chemical and Biological Engineering, Seoul National University, Seoul 151-744, Korea, Department of Physics and Institute of Basic Science, Sungkyunkwan University, Suwon 440-746, Korea, Quantum Material Research Team, Korea Basic Science Institute, Daejeon 305-333, Korea, and School of Materials Science & Engineering and National Research Laboratory of Charged Nanoparticles, Seoul...