1. Department of Physics, Ho Chi Minh City University of Education, Ho Chi Minh City, Vietnam
2. International Training Institute for Materials Science, Hanoi University of Science and Technology, Hanoi, Vietnam
3. Laboratory of Applied Physics, Advanced Institute of Materials Science, Ton Duc Thang University, Ho Chi Minh City, Vietnam
4. Faculty of Applied Sciences, Ton Duc Thang University, Ho Chi Minh City, Vietnam