1. Biophysics Group, Department of Physics, Faculty of Science, Mahidol University, Bangkok, Thailand
2. National Nanotechnology Center (NANOTEC), National Science and Technology Development Agency (NSTDA), Pathum Thani, Thailand
3. Department of Physics, Faculty of Science, Mahidol University, Bangkok, Thailand
4. Centre of Excellence in Mathematics, CHE, Ministry of Education, Bangkok, Thailand