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
Optics
Vladimir M. Stojanovic
Summary: This study demonstrates the creation of scalable entanglement resources in a different physical environment through the engineering of twisted W states in arrays of cold neutral atoms. By utilizing specific laser tuning and effective excitation-boson Hamiltonian, the desired W state can be prepared efficiently.
Article
Physics, Multidisciplinary
Xiao-Feng Shi
Summary: This paper presents two solutions to the challenge of Rydberg excitation in alkaline-earth-like atoms with complicated nuclear spin states. The first theory involves exciting two nuclear spin qubit states to Rydberg states with detuning from a weak magnetic field, while the second theory demonstrates a two-photon Rydberg excitation with only one nuclear spin qubit state. These theories offer a versatile approach to quantum computation leveraging Rydberg blockade and nuclear-spin quantum memory advantages.
FRONTIERS OF PHYSICS
(2021)
Article
Physics, Multidisciplinary
Tommaso Comparin, Fabio Mezzacapo, Martin Robert-de-Saint-Vincen, Tommaso Roscilde
Summary: This article discusses the property of spontaneous symmetry breaking in quantum spin models and demonstrates the realization of spin squeezing through adiabatic processes, providing possibilities for entanglement detection and metrological uses of quantum states.
PHYSICAL REVIEW LETTERS
(2022)
Article
Chemistry, Physical
Jakub Chalupsky, Martin Srnec, Takeshi Yanai
Summary: The analysis of entropy and mutual information may lead to incorrect interpretations of the J-coupling mechanism when investigating exchange interactions between open-shell metal ions. Instead, a new orbital-entanglement analysis based on two-electron density provides a coherent picture of exchange pathways that correlates well with experimental J values. This study highlights the importance of considering spin entanglement in understanding the complexity of wave functions and electron density, particularly in the context of exchange interactions in metal complexes.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Optics
Zhao-Yu Sun, Meng Li, Long-Hui Sheng, Bin Guo
Summary: This paper investigates multipartite nonlocality as an important measure of multipartite quantum correlations. By utilizing matrix product operator and tensor networks, the calculation of nonlocality measure is simplified for various 1D spin chain models. The study reveals interesting behaviors of multipartite nonlocality in finite-temperature regions of these models.
Article
Optics
Zhuo Fu, Peng Xu, Yuan Sun, Yang-Yang Liu, Xiao-Dong He, Xiao Li, Min Liu, Run-Bing Li, Jin Wang, Liang Liu, Ming-Sheng Zhan
Summary: This article reports experimental results on the realization of a two-qubit controlled-PHASE (CZ) gate via single-modulated-pulse off-resonant modulated driving in rubidium (Rb) atoms. The gate operation is completed using a carefully calculated smooth waveform global driving laser pulse and combined with global microwave pulses to generate two-atom entanglement.
Article
Materials Science, Multidisciplinary
Paola Ruggiero, Xhek Turkeshi
Summary: In this paper, we study the spreading of quantum correlations and information in a one-dimensional quantum spin chain with critical disorder. Our focus is on the dynamics after a quantum quench of various entanglement measures in the prototypical XXZ spin chain with random bonds and anisotropy parameters. We provide analytic predictions in the scaling regime based on real-space renormalization-group methods, and support our findings through numerical simulations in the noninteracting limit.
Article
Optics
G. Mouloudakis, T. Ilias, P. Lambropoulos
Summary: In this work, a recursive method for calculating the wave function of an XX spin chain is presented. The method is based on the time-dependent Schrodinger's equations and allows for closed-form solutions of the transformed amplitudes. The results demonstrate the system's dynamics and state-transfer properties for various parameter combinations, with detailed comparisons of Lorentzian and Ohmic reservoirs.
Article
Physics, Multidisciplinary
Bai Wen-Jie, Yan Dong, Han Hai-Yan, Hua Shuo, Gu Kai-Hui
Summary: Rydberg atoms have attracted significant attention in the fields of quantum information and quantum optics due to their long lifetime, easy operability, and controllable interactions. By utilizing the superatom model, this study investigates the in-phase and anti-phase dynamics of three-body Rydberg superatoms and successfully generates W states and two types of maximal entangled states.
ACTA PHYSICA SINICA
(2022)
Article
Materials Science, Multidisciplinary
Rui Mao, Yan-Wei Dai, Sam Young Cho, Huan-Qiang Zhou
Summary: In this study, quantum phase transitions and coherence in infinite biquadratic spin-1 and -2 XY chains with rhombic single-ion anisotropy were investigated. Singular behaviors were identified in the spin-1 system using coherence measures, while the spin-2 system did not exhibit singular behavior in the parameter range. Novel orderings of spin quadrupole moments with zero magnetic moments were found in both systems. Adiabatic connections between orthogonal biaxial spin nematic states in the spin-2 system were observed without explicit phase transitions, while discontinuous quantum phase transitions occurred between distinct uniaxial spin nematic phases in the spin-1 system. Discussions on quantum coherence measures and quantum mutual information in connection with quantum phase transitions including the quantum crossover were also provided.
Article
Physics, Multidisciplinary
Romain Debroux, Cathryn P. Michaels, Carola M. Purser, Noel Wan, Matthew E. Trusheim, Jesus Arjona Martinez, Ryan A. Parker, Alexander M. Stramma, Kevin C. Chen, Lorenzo de Santis, Evgeny M. Alexeev, Andrea C. Ferrari, Dirk Englund, Dorian A. Gangloff, Mete Atature
Summary: The study demonstrates multi-axis coherent control of the SnV spin qubit through all-optical stimulated Raman drive, confirming its coherent access and revealing spin dephasing time and spin coherence time. By integrating SnV into photonic nanostructures, it becomes a competitive spin-photon building block for quantum networks.
Article
Optics
L. V. Gerasimov, R. R. Yusupov, A. D. Moiseevsky, I. Vybornyi, K. S. Tikhonov, S. P. Kulik, S. S. Straupe, C. I. Sukenik, D. V. Kupriyanov
Summary: This article presents a detailed theoretical analysis of the physics underlying the implementation of a Rydberg two-qubit gate using single atoms. The authors focus on a blockade-type entangling gate and consider various decoherence processes that may limit its performance in a real system. Numerical estimates for fidelity limits and predictions for the full process matrix are provided. The study's methods and results are applicable to the simulation and optimization of neutral atom-based quantum processors.
Article
Materials Science, Multidisciplinary
Christopher M. Langlett, Shenglong Xu
Summary: This work introduces a family of spin-1/2 many-body Hamiltonians based on the Fredkin spin chain, featuring a fragmented Hilbert space and quantum many-body scars. Exact middle spectrum eigenstates are constructed to demonstrate logarithmic or area-law entanglement entropy within each fractured subsector. The interplay between fragmentation and scarring results in rich tunable nonergodic dynamics.
Article
Physics, Multidisciplinary
Yanting Cheng, Chengshu Li, Hui Zhai
Summary: Recently, the Rydberg blockade effect has been used to realize quantum spin liquid (QSL) on a kagome lattice, and evidence of QSL has been obtained experimentally by measuring non-local string order. In this paper, a Bardeen-Cooper-Schrieffer (BCS)-type variational wave function study is reported for the spin liquid state in this model, which is motivated by mapping the Rydberg blockade model to a lattice gauge theory. The predictions of this wave function are compared with experimental measurements of non-local string order, and good agreement is found.
NEW JOURNAL OF PHYSICS
(2023)
Article
Chemistry, Physical
Yan Lu, Xiao-Feng Shi, Freddie R. Salsbury, Philippe Derreumaux
JOURNAL OF CHEMICAL PHYSICS
(2018)
Article
Chemistry, Physical
Yan Lu, Xiao-Feng Shi, Phuong H. Nguyen, Fabio Sterpone, Freddie R. Salsbury, Philippe Derreumaux
JOURNAL OF PHYSICAL CHEMISTRY B
(2019)
Article
Physics, Applied
Xiao-Feng Shi
PHYSICAL REVIEW APPLIED
(2019)
Article
Optics
Xiao-Feng Shi
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
(2020)
Article
Physics, Applied
Xiao-Feng Shi
PHYSICAL REVIEW APPLIED
(2020)
Article
Physics, Applied
Xiao-Feng Shi
PHYSICAL REVIEW APPLIED
(2020)
Article
Physics, Multidisciplinary
Xiao-Feng Shi
Summary: This paper presents two solutions to the challenge of Rydberg excitation in alkaline-earth-like atoms with complicated nuclear spin states. The first theory involves exciting two nuclear spin qubit states to Rydberg states with detuning from a weak magnetic field, while the second theory demonstrates a two-photon Rydberg excitation with only one nuclear spin qubit state. These theories offer a versatile approach to quantum computation leveraging Rydberg blockade and nuclear-spin quantum memory advantages.
FRONTIERS OF PHYSICS
(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
Seokho Jeong, Xiao-Feng Shi, Minhyuk Kim, Jaewook Ahn
Summary: Rydberg atom arrays are useful for various quantum applications. In this study, researchers propose an all-optical gate-based quantum computing scheme using auxiliary atoms for remote couplings and optical addressing for constructing universal quantum gates. They also provide a detailed resource estimate for implementing this scheme in a Rydberg quantum simulator.
FRONTIERS IN PHYSICS
(2022)
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
Optics
Xiao-Feng Shi
Summary: We study the entanglement between atoms and microwave photons in a superconducting coplanar waveguide (SCW), which can be used for hybrid quantum devices and connecting static and flying qubits. The gate protocol we propose allows for a one-step controlled-Z(CZ) gate between a neutral atom trapped near the SCW and a microwave mode in the SCW, requiring only one laser pulse for the transition between the ground and Rydberg states of the neutral atom.
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
Xiao-Feng Shi, Yan Lu
Summary: A method for realizing controlled-phase gates and controlled-NOT gates using Rydberg interactions was studied, which can entangle atoms separated by large distances, suitable for large-scale quantum computing.
Article
Optics
Xiao-Feng Shi, T. A. B. Kennedy
Article
Optics
Xiao-Feng Shi
