1. Department of Physical and Chemical Sciences, University of L'Aquila, via Vetoio, 67100 L'Aquila, AQ, Italy
2. Sensor Lab, Department of Information Engineering, University of Brescia, Via Valotti 9, 25133 Brescia, Italy
3. Department of Engineering “Enzo Ferrari”, University of Modena and Reggio Emilia, Via Vivarelli 10, 41125 Modena, Italy
4. National Institute of Materials Physics, Atomistilor 405A, 077125 Magurele, Romania
5. Charles University, V Holesovickăch 2, Prague 8, 18000 Prague, Czech Republic
6. Department of Physics, National Cheng Kung University, 1 Ta-Hsueh Road, 70101 Tainan, Taiwan
7. Taiwan Consortium of Emergent Crystalline Materials, National Science and Technology Council, Taipei 10601, Taiwan
8. College of Science, Institute of Materials Physics and Chemistry, Nanjing Forestry University, Nanjing 210037, P. R. China
9. Institute of Physics and Technology, Ural Federal University, Mira 19 Str., Yekaterinburg 620002, Russia