1. a Department of Physics and Materials Science, Faculty of Science , Chiang Mai University , Chiang Mai , 50200 , Thailand
2. c Thailand Center of Excellence in Physics, Commission on Higher Education, Ministry of Education , Bangkok , 10400 , Thailand
3. b School of Physics, Institute of Science , Suranaree University of Technology and NANOTECH-SUT Center of Excellence on Advanced Functional Nanomaterials , Nakhon Ratchasima , 30000 , Thailand