Department of Physics, Faculty of Science, Mahidol University, Bangkok 10400, Thailand;
Department of Physics, Faculty of Science, Mahidol University, Bangkok 10400, Thailand;
Department of Physics, Faculty of Science, Mahidol University, Bangkok 10400, Thailand;
Department of Material Science, Faculty of Science, Kasetsart University, Bangkok 10900, Thailand;
Department of Physics, Faculty of Science, Kasetsart University, Bangkok 10900, Thailand;