1. Physics Department, Taras Shevchenko National University of Kyiv, 01601 Kyiv, Ukraine
2. Department of Photon Processes, Institute of Physics, National Academy of Sciences of Ukraine, 03028 Kyiv, Ukraine
3. Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, 518060 Shenzhen, China