1. National Key Laboratory of Science and Technology on Tunable Laser, Harbin Institute of Technology, Block 2A, 2 Yikuang St., 150001 Harbin, Peoples Republic of China
2. Institute of Physics, Czech Academy of Sciences, Na Slovance 2, 182 21 Prague, Czech Republic
3. Department of Optical Engineering, School of Astronautics, Harbin Institute of Technology, Block B2, 2 Yikuang St., 150001 Harbin, Peoples Republic of China