1. School of Mathematics and Statistics, and the Center for Post-Doctoral Studies of Management Science and Engineering, Shandong Normal University, Jinan, China
2. School of Mathematics and Statistics, Shandong Normal University, Jinan, China
3. CAS Key Laboratory of Microscale Magnetic Resonance, the School of Physical Sciences, and the CAS Center for Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, China