1 Department of Electrical and Computer Engineering, University of California, Los Angeles, California 90095, United States.
2 Beijing Academy of Quantum Information Sciences, Beijing 100193, China.
3 NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-6102, United States.
4 ICQD, Hefei National Laboratory for Physical Sciences at Microscale, CAS Key Laboratory of Strongly-Coupled Quantum Matter Physics, and Department of Physics, University of Science and Technology of China, Anhui 230026, China.
5 Materials Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-6102, United States.
6 Department of Mechanical and Aerospace Engineering, University of California, Los Angeles, California 90095, United States.
7 College of Physics and Hebei Advanced Thin Film Laboratory, Hebei Normal University, Hebei 050024, China.
8 Department of Physics and Astronomy, University of California, Los Angeles, California 90095, United States.