Scalable quantum computing is based on realizable accurate quantum gates. For neutral atoms, it is an outstanding challenge to design a high-fidelity two-qubit entangling gate without resorting to difficult techniques like shaping laser pulses or cooling atoms to motional ground states. By using spin echo to suppress the blockade error, we propose an easily realizable controlled-phase Rydberg quantum gate of high intrinsic fidelity. In the context of spin echo, we show that the fundamental blockade error of the traditional Rydberg gate, on the order of $ε\sim10^{-3}$, actually results from two `clockwise' rotations of Rabi frequencies $\barΩ_\pm=V\pm \sqrt{V^2+Ω^2}$. In our `echo' sequence, such an error can be suppressed to the order of $ε^2$ by adding two `anticlockwise' rotations with frequencies $-\barΩ_\pm$. With the blockade error effectively removed, the error caused by Rydberg state decay becomes the final fundamental limit to the gate accuracy, which in principle, can be reduced beyond the level of $10^{-5}$. Furthermore, due to the small population $ε$ involved in the `echo' process, the spin-echo gate is robust against the variation of Rydberg blockade caused by the drift of the qubits, so that it can still be much more accurate than that of a traditional Rydberg gate even for qubits cooled only to the sub-mK regime.
Multiplexed storage and interaction of Rydberg spinwaves via the gradient echo memory protocol
Faculty of Physics, University of Warsaw（华沙大学物理学院）；Centre for Quantum Optical Technologies, Centre of New Technologies, University of Warsaw（华沙大学新技术中心量子光学技术中心）
Robust controlled-Z gate for Rydberg atoms based on level-crossing-free echoing rapid adiabatic passage
College of Physics and Electronic Engineering, Shanxi University（山西大学物理电子工程学院）；Collaborative Innovation Center of Extreme Optics, Shanxi University（山西大学极端光学协同创新中心）
Hybrid quantum memory leveraging slow-light and gradient-echo duality
Centre for Quantum Optical Technologies, Centre of New Technologies, University of Warsaw（华沙大学新技术中心量子光学技术研究中心）；Faculty of Physics, University of Warsaw（华沙大学物理学院）
Observation of non-Hermitian many-body phase transition in a Rydberg-atom array
Huazhong University of Science and Technology（华中科技大学）；Shanghai Qi Zhi Institute（上海人工智能实验室）；TU Wien（维也纳工业大学）；The University of Nottingham（诺丁汉大学）；Wuhan Institute of Quantum Technology（武汉量子技术研究院）
Adiabatic echo protocols for robust quantum many-body state preparation
University of Innsbruck（因斯布鲁克大学）；Austrian Academy of Sciences（奥地利科学院）；JILA, University of Colorado and National Institute of Standards and Technology（科罗拉多大学与美国国家标准与技术研究院联合物理科学研究所）；Department of Physics, University of Colorado（科罗拉多大学物理系）
Non-destructive optical read-out and manipulation of circular Rydberg atoms
Laboratoire Kastler Brossel, Collège de France, CNRS, ENS-Université PSL, Sorbonne Université（卡斯特尔-布罗塞尔实验室，法兰西公学院，法国国家科学研究中心，巴黎高等师范学院-巴黎文理研究大学，索邦大学）；Institut Universitaire de France（法兰西学院）
Single-Operation Rydberg Phase Gates via Dynamic Population Suppression
DEVCOM Army Research Laboratory（DEVCOM陆军研究实验室）；Department of Physics, Stevens Institute of Technology（史蒂文斯理工学院物理系）；Departamento de Química Física, Universidad Complutense（康普鲁顿大学物理化学系）
Measurement-Free Toric-Code Memory in Array Globally Controlled Rydberg Array
The Hong Kong University of Science and Technology (Guangzhou)（香港科技大学（广州））；International Quantum Academy, and Shenzhen Branch, Hefei National Laboratory（国际量子学院，合肥国家实验室深圳分部）
Continuously tunable single-photon level nonlinearity with Rydberg state wave-function engineering
Huazhong University of Science and Technology（华中科技大学）；Beijing Automation Control Equipment Institute（北京自动化控制设备研究所）；China Aerospace Science and Industry Corporation（中国航天科工集团）；Chinese Academy of Sciences（中国科学院）；University of Chinese Academy of Sciences（中国科学院大学）；Wuhan Institute of Quantum Technology（武汉量子技术研究院）
Taming Rydberg Decay with Measurement-based Quantum Computation
Hefei National Research Center for Physical Sciences at the Microscale and School of Physical Sciences, University of Science and Technology of China（中国科学技术大学物理科学学院和微观尺度物理国家研究中心）；Shanghai Research Center for Quantum Science and CAS Center for Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China（中国科学技术大学上海量子科学研究中心和中科院量子信息重点实验室）；Hefei National Laboratory, University of Science and Technology of China（中国科学技术大学合肥国家实验室）
