Article
Optics
Tianfeng Feng, Changliang Ren, Qin Feng, Maolin Luo, Xiaogang Qiang, Jing-Ling Chen, Xiaoqi Zhou
Summary: The study formulates the original EPR steering paradox into a contradictory equality, conducts experimental tests in a two-qubit scenario, and confirms that the experimental results coincide with theoretical predictions.
PHOTONICS RESEARCH
(2021)
Article
Physics, Multidisciplinary
Waldemar Klobus, Marek Miller, Mahasweta Pandit, Ray Ganardi, Lukas Knips, Jan Dziewior, Jasmin Meinecke, Harald Weinfurter, Wieslaw Laskowski, Tomasz Paterek
Summary: The study introduces an information-theoretic quantifier to measure the advantage gained from cooperation and the degree of dependency between subsystems of a global system. This quantifier can be directly applied to classical as well as quantum systems and is computed by comparing the conditional mutual information between any two subsystems. Results demonstrate the benefits of using the new quantifier for symmetric quantum secret sharing, and prove the lack of monotonicity of conditional mutual information under local operations.
NEW JOURNAL OF PHYSICS
(2021)
Article
Physics, Multidisciplinary
T. Mueller, S. Diehl, M. Buchhold
Summary: We have identified an unconventional algebraic scaling phase in the quantum dynamics of long-range hopping free fermions under continuous local measurements. This phase exhibits features such as algebraic entanglement entropy growth and a slow algebraic decay of the density-density correlation function.
PHYSICAL REVIEW LETTERS
(2022)
Article
Materials Science, Multidisciplinary
Gregory S. Bentsen, Subhayan Sahu, Brian Swingle
Summary: Competition between unitary dynamics and local measurements in quantum entanglement phase transition is studied using an analytically tractable circuit model. It is found that the measurement rate affects the entanglement preservation in the hybrid system. The second-order phase transition below a critical measurement rate is characterized by a mean-field-like behavior and described in terms of a simple Ising field theory in 0 + 1 dimensions. The study also relates the results to quantum error correction and discusses the experimental feasibility of simulating the averaged purity.
Article
Physics, Multidisciplinary
Karl Pelka, Guilhem Madiot, Remy Braive, Andre Xuereb
Summary: Cavity optomechanical systems enable the manipulation of mechanical degrees of freedom with light. In this study, we demonstrate that temporally modulated driving can steer mechanical modes and induce transitions between different steady states. Our results also reveal the additional influence of thermo-optic nonlinearity on system dynamics.
PHYSICAL REVIEW LETTERS
(2022)
Article
Quantum Science & Technology
Simon J. D. Phoenix, Faisal Shah Khan, Berihu Teklu
Summary: The production and manipulation of quantum correlation protocols is an active area of research, where the quantum nature of the correlation can be used to achieve properties unattainable in a classical framework. This work focuses on measuring the strength of correlation between quantum systems, with a special emphasis on multipartite systems.
QUANTUM INFORMATION PROCESSING
(2021)
Article
Quantum Science & Technology
Hui Li, Ting Gao, Fengli Yan
Summary: In this paper, we investigate the tight monogamy relations of multiparty quantum entanglement. We propose a class of improved lower bounds for the quantum states of multiparty quantum systems that satisfy constraints. We establish tighter monogamy relations in tripartite quantum systems using a new inequality, and generalize these relations to multiparty quantum systems. Furthermore, we provide several conclusions for any multiparty quantum states and prove the tightness of the lower bounds. Detailed examples are also given.
QUANTUM INFORMATION PROCESSING
(2022)
Article
Physics, Multidisciplinary
Deng-Hui Yu, Chang-Shui Yu
Summary: We establish entanglement monotones in terms of an operational approach, showing that any good entanglement quantifier defined on pure states can induce an entanglement monotone for all density matrices, with our proposed monotone being the maximum among those with the same form in pure states. In certain special cases, our proposed entanglement monotones are equivalent to the convex roof construction, giving them an operational meaning.
Article
Materials Science, Multidisciplinary
Xiaofan Zhou, Jian-Song Pan, Suotang Jia
Summary: We investigated the many-body topological physics of interacting fermions in an extended Su-Schrieffer-Heeger (SSH) model using the density-matrix renormalization-group numerical method. The interaction-driven phase transition from the topological insulator phase to the charge density wave (CDW) phase was identified by analyzing various properties. The global phase diagram was mapped, showing nontrivial topological insulator, trivial insulator, and CDW phases. The phase transitions between the CDW phase and topologically trivial or nontrivial phases were found to be continuous, contrary to the first-order phase transitions in the interacting SSH model. The phase diagram of the interacting spinful SSH4 model with attractive or repulsive on-site spin interaction was also presented.
Article
Multidisciplinary Sciences
Roy J. Garcia, Kaifeng Bu, Arthur Jaffe
Summary: Quantum chaos, characterized by the spread of local quantum information called scrambling, has found various applications in physics. This work introduces a mathematical definition of scrambling and a resource theory to measure it, along with two applications. Firstly, the resource theory is used to establish a bound on magic, a potential source of quantum computational advantage that can be efficiently measured in experiments. Secondly, it is shown that scrambling resources limit the success of Yoshida's black hole decoding protocol.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2023)
Article
Quantum Science & Technology
Wen-jing Li, Liang Tang, Qun Zhang, Ming-qiang Bai
Summary: The paper discusses how obtaining information of a quantum system through quantum measurements can bring disturbances to the system and affect the entanglement between arbitrary bipartite systems. By modeling the measurement process as tripartite systems and defining various information quantities, the relationships between information gain and entanglement in the tripartite systems are explored.
QUANTUM INFORMATION PROCESSING
(2021)
Article
Quantum Science & Technology
De-Hua Zhang, Feng-Lin Wu, Zhen-Yu Peng, Lu Wang, Si-Yuan Liu
Summary: In this paper, the genuine multipartite coherence and genuine multipartite average coherence are defined and their properties are discussed. The relationship between these quantities and other quantum resources is investigated. It is found that the genuine multipartite coherence can be represented by interaction information and can determine the existence of genuine multipartite discord. Comparisons are made between global coherence and genuine multipartite coherence in noisy channels with different correlation strengths, and it is observed that both quantities become more stable with increasing correlation strengths, with genuine multipartite coherence being more stable than global coherence. Furthermore, the difference between genuine multipartite coherence and genuine multipartite average coherence is expressed in terms of quantum discord, and it is shown that genuine multipartite coherence is always greater than or equal to genuine multipartite entanglement. Trade-off relations between total correlation, classical correlation, and quantum correlations are provided for tripartite pure states.
QUANTUM INFORMATION PROCESSING
(2023)
Article
Optics
Lin Wu, Liu Ye, Dong Wang
Summary: This research optimizes uncertainty relations by proposing a tighter lower bound and generalizing it to multipartite systems. Experimental results demonstrate that the new bound outperforms the previous one. These findings are significant for the security of quantum key distribution protocols and quantum precision measurements.
Article
Quantum Science & Technology
K. Andrzejewski
Summary: The dynamical aspects of information-theoretic and entropic measures of quantum systems are studied in this article. It is shown that the increase of entropy and dynamics of Fisher information can be directly described and related for the time-dependent harmonic oscillator and charged particle in certain time-varying electromagnetic fields. Various examples are considered to illustrate these results in a elementary form. The integrals of (geodesic) motion associated with some conformal Killing vectors are shown to lead to the Ermakov-Lewis invariants for the considered electromagnetic fields. The dynamics of entanglement entropy of coupled oscillators with continuous time-dependent parameter is explicitly worked out, and the aspects of quantum-classical transition, in particular decoherence, are analyzed. Finally, the behavior of quantum quenches for mutually non-interacting non-relativistic fermions in a harmonic trap in the presence of critical points is studied in detail.
QUANTUM INFORMATION PROCESSING
(2022)
Article
Physics, Multidisciplinary
Jia-Chen Tang, Su-Peng Kou, Gaoyong Sun
Summary: We demonstrate that non-Hermitian biorthogonal many-body phase transitions can be characterized by the enhanced decay of the Loschmidt echo. By numerically studying a non-Hermitian transverse field Ising model, we investigate the quantum criticality through finite-size dynamical scaling of the Loschmidt echo. We determine the equilibrium correlation length critical exponents that are consistent with previous exact diagonalization results. Furthermore, we introduce a simple method to detect quantum phase transitions using the short-time average of the rate function, motivated by the critically enhanced decay behavior of the Loschmidt echo. Our studies illustrate how to detect equilibrium many-body phase transitions using biorthogonal Loschmidt echo, which can be observed in future experiments through quantum dynamics after a quench.
