1. CAS Center for Excellence in Nanoscience Beijing Key Laboratory of Micro‐nano Energy and Sensor Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of Sciences Beijing 101400 P. R. China
2. School of Nanoscience and Technology University of Chinese Academy of Sciences Beijing 100049 P. R. China
3. Center on Nanoenergy Research School of Physical Science and Technology Guangxi University Nanning 530004 P. R. China
4. Microsystem and Terahertz Research Center China Academy of Engineering Physics Chengdu 610200 P. R. China
5. Institute of Electronic Engineering China Academy of Engineering Physics Mianyang 621999 P. R. China
6. School of Electronic and Information Engineering Guangxi Normal University Guilin 541004 P. R. China