1. Department of Optoelectronic Science and Engineering Donghua University Shanghai 201620 China
2. State Key Laboratory for Infrared Physics Shanghai Institute of Technical Physics Chinese Academy of Sciences 500 Yu-tian Road Shanghai 200083 China
3. Research Center for Intelligent Network Zhejiang Lab Hangzhou 311121 China
4. Department of Physics National Cheng Kung University 1 Ta-Hsueh Road 70101 Tainan Taiwan
5. Department of Physics Indian Institute of Technology Kanpur Kanpur 208016 India
6. Department of Industrial and Information Engineering and Economics University of L’Aquila Via G. Gronchi 18 I-67100 L’Aquila Italy
7. College of Science Nanjing Forestry University 159 Longpan Road Nanjing 210037 P. R. China
8. Institute of Physics and Technology Ural Federal University Mira Str. 19 620002 Yekaterinburg Russia
9. Laboratorio TASC Consiglio Nazionale delle Ricerche (CNR)- Istituto Officina dei Materiali (IOM) Area Science Park S.S. 14 km 163.5 34149 Trieste Italy
10. Department of Physical and Chemical Sciences University of L’Aquila via Vetoio 67100 L’Aquila (AQ) Italy
11. Istituto per la Microelettronica e Microsistemi Consiglio Nazionale delle Ricerche VIII strada 5 I-95121 Catania Italy