Article
Optics
Xiao-Feng Shi
Summary: This study focuses on hyperentanglement in individual neutral atoms, demonstrating the controlled-Z operation in electronic and nuclear qubits through the Rydberg blockade effect. This offers opportunities for research in quantum science and technology based on neutral atoms.
Article
Optics
Wei-Lin Mu, Xiao-Xuan Li, Xiao-Qiang Shao
Summary: We propose a cooling scheme to prepare stationary entanglement of neutral atoms in the Rydberg blockade regime by the combination of periodically collective laser pumping and dissipation. This protocol aims to stabilize the system into the desired steady state independently of the initial state, without requiring coherent addressing of individual neutral atoms or fine control of Rydberg interaction intensity, thus improving the feasibility of experiments in related fields.
Article
Physics, Multidisciplinary
Jeremy T. Young, Przemyslaw Bienias, Ron Belyansky, Adam M. Kaufman, Alexey Gorshkov
Summary: Rydberg atoms with strong and tunable interactions can be utilized to realize fast two-qubit entangling gates. A generalization of these gates to multiqubit Rydberg-blockade gates involving many control and target qubits simultaneously is proposed, achieved by using strong microwave fields to dress nearby Rydberg states. The implementation of these multiqubit gates has the potential to simplify quantum algorithms and state preparation, as demonstrated by the creation of a 25-atom Greenberger-Horne-Zeilinger state using only three gates with a 5.8% error rate.
PHYSICAL REVIEW LETTERS
(2021)
Review
Quantum Science & Technology
Xiao-Feng Shi
Summary: This article discusses the significance of quantum gates and entanglement based on dipole-dipole interactions of neutral Rydberg atoms in both fundamental physics and quantum information science. It highlights the precision and robustness of Rydberg-mediated entanglement protocols, which are key factors limiting their applicability in experiments and near-future industry. The article reviews various methods for generating entangling gates by exploring the Rydberg interactions of neutral atoms, and emphasizes the achievable fidelity and robustness to technical issues and detrimental innate factors.
QUANTUM SCIENCE AND TECHNOLOGY
(2022)
Article
Physics, Multidisciplinary
Shiqing Tang, Chong Yang, Dongxiao Li, Xiaoqiang Shao
Summary: In this study, a scheme for rapidly implementing a three-atom Rydberg CCZ gate via a single pulse is proposed, using the Rydberg blockade effect. This gate is successfully applied to quantum algorithms like the Deutsch-Jozsa algorithm and Grover search. The logical states of the gate are encoded to avoid spontaneous emission effects, and individual addressing of atoms is not required in this protocol.
Article
Physics, Applied
Dongmin Yu, Han Wang, Jin-Ming Liu, Shi-Lei Su, Jing Qian, Weiping Zhang
Summary: This paper demonstrates a method for implementing a multiqubit blockade gate using atoms arranged in a three-dimensional spheroidal array. By optimizing the control qubit distributions, an enhanced asymmetric Rydberg blockade is achieved, with robustness and negligible position error. Numerical calculations show that high-fidelity multiqubit quantum computation can be achieved.
PHYSICAL REVIEW APPLIED
(2022)
Article
Quantum Science & Technology
G. Pelegri, A. J. Daley, J. D. Pritchard
Summary: The study proposes a protocol for implementing high-fidelity multiqubit controlled phase gates on neutral atom qubits. The results show that high-fidelity quantum gates can be achieved in a relatively short time period using this protocol. This has potential implications and applications for future developments.
QUANTUM SCIENCE AND TECHNOLOGY
(2022)
Article
Optics
T. H. Xing, P. Z. Zhao, D. M. Tong
Summary: This paper presents a scheme for implementing nonadiabatic holonomic multiqubit controlled gates based on Rydberg atoms, where the Rydberg-mediated interaction couples two qubits and allows for the implementation of quantum gates in a short duration. The effective coupling between two qubits is in the first-order strength of Rabi frequencies, enabling the realization of quantum gates efficiently.
Article
Multidisciplinary Sciences
Julian Heckoetter, Valentin Walther, Stefan Scheel, Manfred Bayer, Thomas Pohl, Marc Assmann
Summary: Researchers demonstrated the generation and control of strong exciton interactions in cuprous oxide semiconductors by producing two distinct quantum states of Rydberg excitons through two-color pump-probe experiments. This led to the emergence of strong spatial correlations and an inter-state Rydberg blockade over remarkably large distances. The semiconductor excitons exhibited universal properties dependent on the interaction potential shape, indicating vastly extended-range and power-law character.
NATURE COMMUNICATIONS
(2021)
Article
Quantum Science & Technology
Nilesh Goel, J. K. Freericks
Summary: By examining the detailed scenario for implementing n-control-qubit Toffoli gates and select gates on ion-trap quantum computers, we estimated their expected performance and errors. While there are challenges with implementing these gates, as their performance always has some degree of error, they should be feasible on current hardware, but may be too slow for efficient use in quantum codes on noisy intermediate scale quantum computers.
QUANTUM SCIENCE AND TECHNOLOGY
(2021)
Article
Physics, Multidisciplinary
Jin-Lei Wu, Yan Wang, Jin-Xuan Han, Shi-Lei Su, Yan Xia, Yongyuan Jiang, Jie Song
Summary: A dynamics regime of Rydberg atoms called unselective ground-state blockade (UGSB) is proposed to implement a one-step SWAP gate without individual addressing of atoms in the context of Rydberg antiblockade (RAB). This work modifies the RAB condition to achieve a dynamical and robust SWAP gate, and further investigates the implementation of a three-atom Fredkin gate based on the proposed SWAP gates.
FRONTIERS OF PHYSICS
(2022)
Article
Optics
Anupam Mitra, Sivaprasad Omanakuttan, Michael J. Martin, Grant W. Biedermann, Ivan H. Deutsch
Summary: This paper revisits the implementation of a two-qubit entangling gate called Mt lmer-St rensen gate using adiabatic Rydberg dressing for neutral atoms. The study shows that rapid adiabatic passage can be achieved through a two-photon transition without the need for an ultraviolet laser, by simply modulating the amplitude of one field with fixed laser frequencies. The results demonstrate that entangling gate fidelities comparable to the one-photon excitation can be achieved with the two-photon excitation. Furthermore, the paper explores how the adiabatic dressing protocol can be used to implement entangling gates beyond the regime of a perfect Rydberg blockade, allowing for fast high-fidelity gates for atoms separated beyond the blockade radius.
Article
Optics
J-F Wei, F-Q Guo, D-Y Wang, Y. Jia, L-L Yan, M. Feng, S-L Su
Summary: This article introduces a fast-operation scheme for geometric multiqubit fan-out gates, using asymmetric Rydberg-Rydberg interaction and time-optimal control technology. The scheme features nonadiabaticity and generality, providing scalability and fault tolerance in Rydberg-based quantum computing.
Article
Optics
Chi-En Wu, Teodora Kirova, Marcis Auzins, Yi-Hsin Chen
Summary: In this theoretical study, the enhancement of the Rydberg blockade radius using Forster resonance is presented. The investigation reveals that significant differences in the principal quantum numbers of two Rydberg states can substantially improve the blockade radius, exceeding 50 μm.
Article
Optics
Yang Zhao, Xiao-Feng Shi
Summary: Topological nontrivial bands can be realized via Rydberg-dressed neutral atoms. By studying a two-dimensional hard-core boson model on a honeycomb array, it is found that a fractional Chern insulator phase with Chern number C = 1/2 can exist in the system, even in the presence of weak many-body interactions.
Article
Physics, Multidisciplinary
Wan-Jun Su, Guang-Zheng Ye, Ya-Dong Wu, Zhen-Biao Yang, Barry C. Sanders
Summary: In this study, we propose a scheme to achieve nuclear-nuclear indirect interactions mediated by a mechanically driven nitrogen-vacancy (NV) center in a diamond. We demonstrate experimental results of two-qubit entangling gates and quantum-state transfer, and find that the scheme is robust against decoherence caused by coupling between the NV center (nuclear spins) and the environment, and insensitive to fluctuating positions of the nuclear spins and the NV center. This scheme provides a general blueprint for multi-nuclear-spin gates and multi-party communication.
COMMUNICATIONS IN THEORETICAL PHYSICS
(2022)
Article
Optics
Yan-Ting Lan, Wan-Jun Su, Huaizhi Wu, Yong Li, Shi-Biao Zheng
Summary: In this paper, we study optomechanically induced directional amplification and isolation in a generic setup including two cavities and two mechanical oscillators by exclusively using blue-sideband drive tones. By choosing appropriate transfer phases and strengths of the driving fields, both directional amplification and isolation with bi-directional nonreciprocity can be achieved.
Article
Optics
Shou-Bang Yang, Wen Ning, Ri-Hua Zheng, Zhen-Biao Yang, Shi-Biao Zheng
Summary: This paper proposes an experimentally feasible scheme to achieve deterministic entanglement swapping in hybrid systems with discrete and continuous variables. The scheme involves preparing entangled states, performing a Bell-state analysis, and projecting the qubits.
Article
Physics, Multidisciplinary
Ri-Hua Zheng, Wen Ning, Zhen-Biao Yang, Yan Xia, Shi-Biao Zheng
Summary: This article presents a method for dynamical control in three-level open systems and demonstrates its implementation in an experiment with a superconducting qutrit. The results show that in a Markovian environment, the populations or coherence of the system can still strictly follow the preset evolution paths for a relatively long time (3 μs). This experiment is the first to precisely control the Markovian dynamics of three-level open systems, providing a solid foundation for future dynamical control in multiple open systems. An immediate application of this technique is to stabilize the energy of quantum batteries.
NEW JOURNAL OF PHYSICS
(2022)
Article
Physics, Multidisciplinary
Huaizhi Wu, Xin-Yu Lin, Zong-Xing Ding, Shi-Biao Zheng, Igor Lesanovsky, Weibin Li
Summary: We propose a Rydberg molecule dressing scheme that can generate strong and long-range interactions at selective distances. By coupling ground-state atoms off-resonantly to two interacting Rydberg atoms on an attractive molecular curve, we can control the ratio of dressed interaction to dephasing rate at large atomic separations. This scheme enables the fast generation of spin squeezing and provides a new route for studying complex many-body dynamics and realizing quantum information processing with non-convex long-range interactions.
SCIENCE CHINA-PHYSICS MECHANICS & ASTRONOMY
(2022)
Article
Optics
Chun-Wang Liu, Ye Liu, Lei Du, Wan-Jun Su, Huaizhi Wu, Yong Li
Summary: In this article, we study the enhanced sensing of optomechanically induced nonlinearity (OMIN) in a cavity-waveguide coupled system. By introducing weak waveguide-mediated coherent coupling, we find a strong bistable response of the cavity intensity to the OMIN near the cavity resonance. This enhanced sensitivity, measured by an enhancement factor, is resistant to cavity decay and fluctuations in the cavity-waveguide detuning.
Article
Multidisciplinary Sciences
Zhongchu Ni, Sai Li, Xiaowei Deng, Yanyan Cai, Libo Zhang, Weiting Wang, Zhen-Biao Yang, Haifeng Yu, Fei Yan, Song Liu, Chang-Ling Zou, Luyan Sun, Shi-Biao Zheng, Yuan Xu, Dapeng Yu
Summary: Quantum error correction (QEC) protects logical qubits by using a large Hilbert space with redundancy to detect and correct errors in real time. In this study, a QEC procedure was demonstrated in a circuit quantum electrodynamics architecture, where a logical qubit was encoded in photon-number states of a microwave cavity and coupled to an auxiliary superconducting qubit. By applying a tailored frequency comb pulse, error syndrome was extracted and error correction was performed, exceeding the break-even point by about 16% lifetime enhancement. This work illustrates the potential of hardware-efficient discrete-variable encodings for fault-tolerant quantum computation.
Article
Physics, Multidisciplinary
Jingwen Yang, Zhicheng Shi, Zhen-Biao Yang, Li-tuo Shen, Shi-Biao Zheng
Summary: Quantum phase transition and entanglement in the Rabi model with squeezed light were investigated. A special unitary-transformation method was found to remove nonintegrable squeezing and counter-rotating wave interactions when the qubit frequency is close to the field frequency. The analytical ground state agrees well with the numerical solution. It was demonstrated that the ground state exhibits a first-order quantum phase transition induced linearly by the squeezed light. This quantum phase transition does not require multiple qubits or an infinite ratio of qubit frequency to field frequency, addressing a critical problem in the theory and experiment of the Rabi model. As the qubit-field coupling strength increases, the ground-state entanglement reaches its maximum value at the critical point.
Article
Physics, Multidisciplinary
Xin Zhu, Jia-Hao Lue, Wen Ning, Fan Wu, Li-Tuo Shen, Zhen-Biao Yang, Shi-Biao Zheng
Summary: This study generalizes the dynamic framework for criticality-enhanced quantum sensing by the quantum Rabi model to its anisotropic counterpart and derives the corresponding analytical expressions for the quantum Fisher information. The results show that the contributions of the rotating-wave and counterrotating-wave interaction terms are symmetric at the limit of the infinite ratio of qubit frequency to field frequency, and the quantum Fisher information reaches a maximum for the isotropic QRM. At finite frequency scaling, the study analytically derives the inverted variance of higher-order correction and finds that it is more affected by the rotating-wave coupling than by the counterrotating-wave coupling.
SCIENCE CHINA-PHYSICS MECHANICS & ASTRONOMY
(2023)
Article
Quantum Science & Technology
Xin-Jie Huang, Pei-Rong Han, Wen Ning, Shou-Bang Yang, Xin Zhu, Jia-Hao Lue, Ri-Hua Zheng, Hekang Li, Zhen-Biao Yang, Kai Xu, Chui-Ping Yang, Qi-Cheng Wu, Dongning Zheng, Heng Fan, Shi-Biao Zheng
Summary: Quantum entanglement between an interfering particle and a detector for acquiring the which-path information plays a central role for enforcing Bohr's complementarity principle. However, the quantitative relation between this entanglement and the fringe visibility remains untouched upon for an initial mixed state. Here we find an equality for quantifying this relation. Our equality characterizes how well the interference pattern can be preserved when an interfering particle, initially carrying a definite amount of coherence, is entangled, to a certain degree, with a which-path detector. This equality provides a connection between entanglement and interference in the unified framework of coherence, revealing the quantitative entanglement-interference complementarity. We experimentally demonstrate this relation with a superconducting circuit, where a resonator serves as a which-path detector for an interfering qubit. The measured fringe visibility of the qubit's Ramsey signal and the qubit-resonator entanglement exhibit a complementary relation, in well agreement with the theoretical prediction.
NPJ QUANTUM INFORMATION
(2023)
Article
Optics
Ling-Shan Lin, Hao-Long Zhang, Zhen-Biao Yang
Summary: Geometry, as a fundamental concept, is widely applied in understanding physical phenomena. In the field of quantum mechanics, the quantum geometric tensor (QGT) is used to characterize the relationship between geometry and the quantum state of a system. Previous research has focused on extracting the quantum metric tensor (QMT) using discrete variables, but there is a lack of research using continuous variables. In this study, a method to extract the QMT of a continuous variable system, specifically a cat-qubit, is proposed by constructing a Kerr nonlinear parametric oscillator (KNPO). This method opens the door for exploring geometry in continuous variable systems.
Article
Quantum Science & Technology
Bi-Yao Wang, Hao-Long Zhang, Shou-Bang Yang, Fan Wu, Zhen-Biao Yang, Shi-Biao Zheng
Summary: This paper proposes a scheme for measuring topological properties in a two-photon-driven Kerr-nonlinear (KNR) resonator subjected to a single-photon modulation. The topological properties are revealed through the observation of the Berry curvature and the first Chern number as a nonadiabatic response of the physical observable to the change rate of the control parameter. The parameter manifold constructed from the system's Hamiltonian indicates a topological transition when the degeneracy crosses the manifold. The scheme, utilizing continuous variable states in mesoscopic systems, offers a new perspective for exploring the geometry and topology of complex systems.
ADVANCED QUANTUM TECHNOLOGIES
(2023)
Article
Quantum Science & Technology
Wen Ning, Ri-Hua Zheng, Yan Xia, Kai Xu, Hekang Li, Dongning Zheng, Heng Fan, Fan Wu, Zhen-Biao Yang, Shi-Biao Zheng
Summary: This study reveals a more fundamental and universal interference behavior beyond Zitterbewegung in phase space for Dirac particles, which is confirmed by both numerical simulation and on-chip experiment. This discovery is of fundamental importance in science and holds potential applications in quantum technology.
NPJ QUANTUM INFORMATION
(2023)
Article
Optics
Jia-Hao Lu, Wen Ning, Xin Zhu, Fan Wu, Li-Tuo Shen, Zhen-Biao Yang, Shi-Biao Zheng
Summary: Quantum sensing improves measurement accuracy by utilizing the unique properties of quantum systems. This study explores an alternative approach to construct a quantum Rabi model analog for sensing, by exploiting the criticality appearing in the Jaynes-Cummings model, thus relaxing the implementation requirements to some extent.
Article
Optics
Li-Tuo Shen, Chun-Qi Tang, Zhicheng Shi, Huaizhi Wu, Zhen-Biao Yang, Shi-Biao Zheng
Summary: Quantum phase transition and quench dynamics in the Jaynes-Cummings model with squeezed light were investigated, where a special unitary transformation was found to remove nonintegrable squeezing interaction. Eigenenergies and eigenstates of normal and superradiant phases were derived analytically, demonstrating a second-order quantum phase transition induced nonlinearly at the phase boundary by squeezed light. Entanglement entropy approached its maximum value as squeezing strength increased in the superradiant phase, and a nonlinear relationship between residual energy and squeezing strength was analytically obtained in quench dynamics.
