1. Songshan Lake Materials Laboratory (SLAB) Dongguan 523808 P. R. China
2. Clean Energy Cluster International Iberian Nanotechnology Laboratory (INL) Avenida Mestre Jose Veiga Braga 4715‐330 Portugal
3. Department of Physical and Chemical Sciences University of L'Aquila via Vetoio L'Aquila (AQ) 67100 Italy
4. Department of Physics National Cheng Kung University 1 Ta‐Hsueh Road Tainan 70101 Taiwan
5. Consortium of Emergent Crystalline Materials National Science and Technology Council Taipei 10601 Taiwan
6. CNR‐IMM Istituto per la Microelettronica e Microsistemi VIII strada 5 Catania I‐95121 Italy
7. College of Science Institute of Materials Physics and Chemistry Nanjing Forestry University Nanjing 210037 P. R. China