1. Ultrafast Electron Microscopy Laboratory The MOE Key Laboratory of Weak‐Light Nonlinear Photonics School of Physics Nankai University Tianjin 300071 China
2. Laboratoire d'Optoélectronique Quantique École Polytechnique Fédérale de Lausanne (EPFL) Station 3 Lausanne CH‐1015 Switzerland
3. Grenoble INP, Institut Néel, CNRS University Grenoble Alpes Grenoble 38000 France
4. State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano‐optoelectronics School of Physics Peking University Beijing 100871 China
5. Peking University Yangtze Delta Institute of Optoelectronics Nantong Jiangsu 226010 China
6. Shenzhen Institute for Quantum Science and Engineering and Department of Physics Southern University of Science and Technology Shenzhen 518055 China