. 00 32 0 v 1 [ qu an tph ] 1 M ay 2 01 9 Observation of multi-component atomic Schrödinger cat states of up to 20 qubits

Chao Song, Kai Xu, Hekang Li, Yuran Zhang, Xu Zhang, Wuxin Liu, Qiujiang Guo, Zhen Wang, Wenhui Ren, Jie Hao, Hui Feng, Heng Fan, Dongning Zheng, Dawei Wang, H. Wang, and Shiyao Zhu 1 Interdisciplinary Center for Quantum Information and Zhejiang Province Key Laboratory of Quantum Technology and Device, Department of Physics, Zhejiang University, Hangzhou 310027, China, 2 Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China, 3 Institute of Automation, Chinese Academy of Sciences, Beijing 100190, China, 4 CAS Center for Excellence in Topological Quantum Computation, University of Chinese Academy of Sciences, Beijing 100190, China, 5 Beijing Computational Science Research Center, Beijing 100094, China, 6 Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, China (Dated: May 2, 2019)