1. State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institude of Laser Spectroscopy
2. College of Physics and Electronics Engineering
3. Shanxi University
4. Taiyuan 030006
5. China
6. St. Petersburg State University
7. St. Petersburg 199034
8. Russia
9. School of Physical Sciences
10. Indian Association for the Cultivation of Science
11. Jadavpur
12. Kolkata 700032
13. India