Affiliation: | 1 School of Electronic Engineering, Tianjin University of Technology and Education, Tianjin 300222, China 2 CNR-SPIN and Dipartimento di Fisica, Universita degli Studi di Napoli Federico II, Complesso Universitario Monte S. Angelo, Via Cintia, Napoli 80126, Italy 3 Ultrafast Laser Lab, Key Laboratory of Opto-electronic Information Technology, Ministry of Education (Tianjin University), Tianjin 300072, China 4 Department and Institute of Physics, School of Science. Tianjin Polytechnic University, Tianjin 300387, China) |