Article
Materials Science, Multidisciplinary
Matthias Christandl, Fulvio Gesmundo, Daniel Stilck Franca, Albert H. Werner
Summary: Tensor network states are a widely used variational ansatz class in the study of quantum many-body systems. Recent work shows that states on the boundary of the tensor network variety can provide more efficient representations for states of interest. By defining a class of states that includes boundary states, it is possible to optimize over this class to find ground states of local Hamiltonians with favorable energies and runtimes.
Article
Quantum Science & Technology
Noa Feldman, Augustine Kshetrimayum, Jens Eisert, Moshe Goldstein
Summary: We introduce a method for extracting meaningful entanglement measures of tensor network states in general dimensions. The method involves stochastic sampling of matrix elements to calculate their moments, providing Renyi entropies and negativities. The method is tested on the one-dimensional critical XX chain and the two-dimensional toric code, showing satisfactory results.
Article
Optics
Stefanie Czischek, Giacomo Torlai, Sayonee Ray, Rajibul Islam, Roger G. Melko
Summary: This study explores novel physics in circuit models involving entangling unitary dynamics and disentangling measurements. Using tensor network simulations, it reveals a transition from volume-law to area-law in entanglement entropy, suggesting universal features of a measurement-induced phase transition. The research highlights the robustness of this transition against experimental noise and emphasizes the role of tensor network simulations in advancing critical phenomena.
Article
Optics
Joseph C. Szabo, Nandini Trivedi
Summary: This study investigates competing entanglement dynamics between a one-dimensional Ising spin chain and an external ancilla qudit system. The results show that the entanglement entropy of the ancilla can track the dynamical phase transition in the underlying spin system. It is found that purely spin-spin entanglement metrics decay as the entanglement entropy of the ancilla increases. The study also introduces the concept of multipartite entanglement loss (MEL), which quantifies the effect of the ancilla on the development of spin-spin entanglement.
Article
Physics, Multidisciplinary
Marcin Plodzien, Maciej Lewenstein, Emilia Witkowska, Jan Chwedenczuk
Summary: We demonstrate that one-axis twisting (OAT) is a powerful source of many-body Bell correlations for creating nonclassical states of bosonic qubits. We develop an analytical and universal treatment that allows us to identify the critical time for the emergence of Bell correlations and predict their depth at subsequent times. Our findings are illustrated using a highly nontrivial example of OAT dynamics generated with the Bose-Hubbard model.
PHYSICAL REVIEW LETTERS
(2022)
Article
Optics
Stefan Floerchinger, Tobias Haas, Henrik Mueller-Groeling
Summary: The Wehrl entropy is discussed in relation to entropic uncertainty relations and quantification of entanglement in continuous variables. It is shown that the Wehrl-Lieb inequality is closer to equality than the usual Bialynicki-Birula-Mycielski entropic uncertainty relation almost everywhere. Additionally, the Wehrl mutual information is demonstrated to be useful in obtaining a measurable perfect witness for pure state bipartite entanglement and providing a lower bound on the entanglement entropy.
Article
Optics
Martin Gaerttner, Tobias Haas, Johannes Noll
Summary: The study demonstrates the universality of continuous variable entanglement criteria based on the Husimi Q distribution through a theorem by Lieb and Solovej, showing their general nature and optimization potential in continuous majorization theory. The derived criteria are compared with marginal-based criteria and the strength of the phase-space approach is highlighted for detecting entanglement in certain example states. Furthermore, optimization prospects are explored in experimentally relevant scenarios with sparse data, leading to clear improvements in detecting a wider range of states and enhancing the signal-to-noise ratio.
Article
Physics, Multidisciplinary
Ivan Bardet, Angela Capel, Li Gao, Angelo Lucia, David Perez-Garcia, Cambyse Rouze
Summary: This paper proves that spin chains weakly coupled to a large heat bath thermalize rapidly at any temperature for finite-range, translation-invariant commuting Hamiltonians, reaching equilibrium in a time which scales logarithmically with the system size. This generalizes to the quantum regime a seminal result of Holley and Stroock from 1989 for classical spin chains and represents an exponential improvement over previous bounds based on the nonclosure of the spectral gap. We discuss the implications in the context of dissipative phase transitions and in the study of symmetry protected topological phases.
PHYSICAL REVIEW LETTERS
(2023)
Article
Physics, Mathematical
Fumio Hiai
Summary: This paper revisits and improves the joint concavity/convexity and monotonicity properties of quasi-entropies proposed by Petz. The authors characterize the equality cases in the monotonicity inequalities of quasi-entropies and provide equivalent conditions for the equality to hold. They also discuss the equality conditions for monotone metrics and chi(2)-divergences, and consider linear preserver problems for these quantum information quantities.
JOURNAL OF MATHEMATICAL PHYSICS
(2023)
Article
Astronomy & Astrophysics
Natalie Klco, Martin J. Savage
Summary: Research shows that there is an exponential decay upper limit to distillable entanglement between two disconnected regions of massless noninteracting scalar field theory. Through lattice calculations, the geometric decay constant between a pair of disks in two spatial dimensions and the growth of the negativity sphere towards the continuum were determined.
Article
Materials Science, Multidisciplinary
Yong-Yi Wang, Zheng-Hang Sun, Heng Fan
Summary: Recent research has shown a disorder-free many-body localization (MBL), known as Stark MBL, in an interacting system with a linear potential. The study investigates Stark MBL in two types of superconducting circuits and calculates entanglement entropy and participate entropy of highly excited eigenstates. The findings suggest that superconducting circuits are a promising platform for studying the critical properties of the Stark MBL transition.
Article
Physics, Multidisciplinary
Xiang Zhou, Zhu-Jun Zheng
Summary: Observational entropy is a generalization of Boltzmann entropy to quantum mechanics and is related to other quantum information measures. Quantum correlation entropy and quantum discord are physical quantities used to measure quantum correlation, based on different observational methods.
EUROPEAN PHYSICAL JOURNAL PLUS
(2022)
Article
Materials Science, Multidisciplinary
Michael O. Flynn, Long-Hin Tang, Anushya Chandran, Chris R. Laumann
Summary: Momentum space entanglement entropy is sensitive to interactions and can probe quantum correlations in interacting fermionic phases. It follows volume-law scaling in general, but vanishes in the Fermi gas. The Renyi entropy in momentum space can be systematically expanded in terms of the phase space volume of the partition, allowing for controlled computation of entropy near the Fermi wave vector in isotropic Fermi liquids and BCS superconductors. It can be accessed in cold atomic and molecular gas experiments through a time-of-flight generalization of previous measurement protocols.
Article
Physics, Multidisciplinary
Francesco Buscemi, Joseph Schindler, Dominik Safranek
Summary: Observational entropy provides a general notion of quantum entropy that interpolates between Boltzmann's and Gibbs' entropies and is useful for measuring out-of-equilibrium thermodynamic entropy. This study focuses on the mathematical properties of observational entropy from an information-theoretic perspective, using strengthened monotonicity properties of quantum relative entropy. The concept of a 'coarse-grained' state, derived from measurement statistics through Bayesian retrodiction, plays a central role in this work and allows for upper and lower bounds on the difference between observational and von Neumann entropies.
NEW JOURNAL OF PHYSICS
(2023)
Article
Physics, Multidisciplinary
Zahra Baghali Khanian, Manabendra Nath Bera, Arnau Riera, Maciej Lewenstein, Andreas Winter
Summary: We extend the previous results on quantum thermodynamics to the case of multiple non-commuting charges and develop a resource theory of thermodynamics for asymptotically many non-interacting systems. The phase diagram of the system is formed by associating the vector of expected charge values and entropy with every state. Our key result is the Asymptotic Equivalence Theorem, which connects the equivalence classes of states under asymptotic charge-conserving unitaries with the points on the phase diagram. Using the phase diagram, we analyze the first and second laws of thermodynamics and provide insights into the storage of different charges in physically separate batteries.
ANNALES HENRI POINCARE
(2023)
Article
Computer Science, Information Systems
Samad Khabbazi Oskouei, Stefano Mancini, Andreas Winter
Summary: Passive environment-assisted communication is investigated in terms of information transmission capabilities. Gaussian unitaries acting on Bosonic systems are considered for both quantum and classical communication. Coding theorems are proved, and an uncertainty-type relation between the classical capacities of the sender and the helper is derived, providing lower bounds on the classical information transmission rate.
IEEE TRANSACTIONS ON INFORMATION THEORY
(2022)
Article
Physics, Multidisciplinary
Zahra Baghali Khanian, Manabendra Nath Bera, Arnau Riera, Maciej Lewenstein, Andreas Winter
Summary: We extend the previous results on quantum thermodynamics to the case of multiple non-commuting charges and develop a resource theory of thermodynamics for asymptotically many non-interacting systems. The phase diagram of the system is formed by associating the vector of expected charge values and entropy with every state. Our key result is the Asymptotic Equivalence Theorem, which connects the equivalence classes of states under asymptotic charge-conserving unitaries with the points on the phase diagram. Using the phase diagram, we analyze the first and second laws of thermodynamics and provide insights into the storage of different charges in physically separate batteries.
ANNALES HENRI POINCARE
(2023)
Article
Nanoscience & Nanotechnology
Beihan Zhao, Vishal Sankar Sivasankar, Swarup Kumar Subudhi, Abhijit Dasgupta, Siddhartha Das
Summary: In this study, we demonstrated the humidity-sensing ability and robustness of syringe-printed single-walled carbon nanotube-graphene oxide (SWCNT-GO) traces on adhesive and flexible PET thin films. The printed traces showed high humidity sensitivity and could be deployed on surfaces with different curvatures. The SWCNT-GO traces exhibited enhanced humidity sensitivity due to the hygroscopic swelling of GO flakes under humid conditions. Furthermore, the traces demonstrated long-term stability and reliable performance even after temperature cycling tests.
ACS APPLIED NANO MATERIALS
(2023)
Review
Materials Science, Multidisciplinary
P. Siva Prasad, Bharat C. G. Marupalli, Siddhartha Das, Karabi Das
Summary: Calcium phosphates, such as hydroxyapatite (HAp), are widely used biomaterials for bone tissue repair. Surfactants have been utilized as templates to control the morphology and size of synthetic HAp particles. This review explores the effects of different chemical and biosurfactants on the structural and biological properties of surfactant-assisted HAp particles.
JOURNAL OF MATERIALS SCIENCE
(2023)
Article
Chemistry, Physical
Bhargav Sai Chava, Ghansham Rajendrasingh Chandel, Siddhartha Das
Summary: In this study, we report the entropy-driven filling of mildly hydrophilic boron nitride nanotubes (BNNTs) with water, which is governed by the unique structure and diameter of the nanotubes. The rotational and translational entropy components play a crucial role in the filling process, with the specific contribution depending on the diameter of the BNNTs and the structure of the water molecules.
JOURNAL OF PHYSICAL CHEMISTRY C
(2023)
Article
Multidisciplinary Sciences
Pavel Hrmo, Benjamin Wilhelm, Lukas Gerster, Martin W. van Mourik, Marcus Huber, Rainer Blatt, Philipp Schindler, Thomas Monz, Martin Ringbauer
Summary: Quantum information carriers naturally occupy high-dimensional Hilbert spaces, and high-dimensional (qudit) quantum systems are becoming a powerful resource for quantum processors. Generating the desired interaction efficiently in these systems is crucial. In this study, the authors demonstrate the implementation of a native two-qudit entangling gate up to dimension 5 in a trapped-ion system. They use a light-shift gate mechanism to generate genuine qudit entanglement in a single application of the gate, which seamlessly adapts to the local dimension of the system with a calibration overhead independent of the dimension. Native entangling techniques for qudits are important for encoding quantum information.
NATURE COMMUNICATIONS
(2023)
Article
Physics, Multidisciplinary
Lukas Bulla, Matej Pivoluska, Kristian Hjorth, Oskar Kohout, Jan Lang, Sebastian Ecker, Sebastian P. Neumann, Julius Bittermann, Robert Kindler, Marcus Huber, Martin Bohmann, Rupert Ursin
Summary: Entanglement distribution via photons over long distances enables many applications, including quantum key distribution. The degradation of entanglement remains a challenge due to noise accumulation. This study presents a long-range free-space quantum link that distributes entanglement over 10.2 km with flexible dimensionality of encoding. The approach utilizes high-dimensional entangled photons and analyzes the achievable key rate in a dimensionally adaptive quantum key distribution protocol.
Article
Quantum Science & Technology
Shuheng Liu, Qiongyi He, Marcus Huber, Otfried Guhne, Giuseppe Vitagliano
Summary: We propose a method to detect the dimensionality of entanglement using correlations between measurements in randomized directions. By deriving an inequality based on the covariance matrix criterion, which is invariant under local changes of su(d) bases, we can find regions in the space of randomized correlations moments that determine the different dimensionalities of entanglement. Our method shows promising results in practical scenarios and can detect more states than existing criteria, making it a powerful and potentially simpler approach. Future work should focus on implementing this method in multipartite scenarios.
Article
Computer Science, Information Systems
Manideep Mamindlapally, Andreas Winter
Summary: This article discusses the derivation of Singleton bounds on the performance of entanglement-assisted hybrid classical-quantum error correcting codes using quantum Shannon theoretic methods. It shows that the triple-rate region of possible EACQ codes is contained within the quantum Shannon theoretic rate region of a memoryless erasure channel, which is a polytope. The study demonstrates that a large part of this region can be achieved by certain EACQ codes under certain conditions.
IEEE TRANSACTIONS ON INFORMATION THEORY
(2023)
Article
Optics
Lukas Bulla, Kristian Hjorth, Oskar Kohout, Jan Lang, Sebastian Ecker, Sebastian P. Neumann, Julius Bittermann, Robert Kindler, Marcus Huber, Martin Bohmann, Rupert Ursin, Matej Pivoluska
Summary: Our study investigates the presence of high-dimensional entanglement in a recent demonstration of a noise-resistant quantum key distribution (QKD) protocol. We found that the distributed entangled states can be certified to have at least three dimensions. To show this, we developed an energy-time entanglement discretization technique and an improved witness for entanglement dimensionality. Our results provide insight into the complex relationship between high-dimensional entanglement and the noise resistance of QKD protocols operating in high dimensions.
Correction
Optics
Karol Horodecki, Marek Winczewski, Siddhartha Das
Article
Fisheries
Andreas Winter, Alexander Arkhipkin
Summary: Data from surveys conducted in 2013, 2018, 2019, and 2021 were analyzed to investigate changes in skate biomass in waters around the Falkland Islands. The surveys showed a decrease in estimated commercial-size skate biomass for most species and overall. This decline was observed both in areas closed to skate fishing and those open to target fishing, indicating the impact of bycatch in finfish trawls.
Article
Quantum Science & Technology
Zi-Wen Liu, Andreas Winter
Summary: Understanding and studying the magic in quantum computation and physics is essential to comprehend quantum complexity. This study examines the magic in strongly entangled many-body quantum states, particularly in systems with multiple qubits. The research finds that the maximum magic of an n-qubit state is closely related to the number of qubits, and nearly all pure n-qubit states have magic values close to n. The analysis also connects the magic of hypergraph states with the nonlinearity of Boolean functions and applies the concept of magic to measurement-based quantum computation and condensed matter systems.
Article
Optics
Farzin Salek, Masahito Hayashi, Andreas Winter
Summary: Adaptiveness is a key principle in information processing, and this study investigates its usefulness in asymptotic binary hypothesis testing for quantum channels. The results show that adaptive and nonadaptive strategies have the same error exponents for classical-quantum channels, and adaptive strategies do not outperform nonadaptive strategies when restricted to classical feed-forward and product state channel inputs.
Article
Optics
Karol Horodecki, Marek Winczewski, Siddhartha Das
Summary: In this paper, several general upper bounds on the rate of a key secure against a quantum adversary in the device-independent conference key agreement (DI-CKA) scenario are provided. These bounds include reduced entanglement measures and multipartite secrecy monotones such as reduced c-squashed entanglement. The comparison between the DI-CKA rate and the device-dependent rate is discussed, with examples demonstrating the strict gap inherited from the bipartite gap between device-independent and device-dependent key rates.
Article
Mathematics, Applied
Muhammad Syifa'ul Mufid, Ebrahim Patel, Sergei Sergeev
Summary: This paper presents an approach to solve maxmin-omega linear systems by performing normalization and generating a principal order matrix. The possible solution indices can be identified using the principal order matrix and the parameter omega, and the fully active solutions can be obtained from these indices. Other solutions can be found by applying a relaxation to the fully active solutions. This approach can be seen as a generalization of solving max-plus or min-plus linear systems. The paper also highlights the unusual feature of maxmin-omega linear systems having a finite number of solutions when the solution is non-unique.
LINEAR ALGEBRA AND ITS APPLICATIONS
(2024)
Article
Mathematics, Applied
E. Mainar, J. M. Pena, B. Rubio
Summary: A bidiagonal decomposition of quantum Hilbert matrices is obtained and the total positivity of these matrices is proved. This factorization is used for accurate algebraic computations and the numerical errors caused by imprecise computer arithmetic or perturbed input data are analyzed. Numerical experiments demonstrate the accuracy of the proposed methods.
LINEAR ALGEBRA AND ITS APPLICATIONS
(2024)
Article
Mathematics, Applied
Zhong-Zhi Bai
Summary: This study explores the algebraic structures and computational properties of Wasserstein-1 metric matrices. It shows that these matrices can be expressed using the Neumann series of nilpotent matrices and can be accurately and stably computed by solving unit bidiagonal triangular systems of linear equations.
LINEAR ALGEBRA AND ITS APPLICATIONS
(2024)
Article
Mathematics, Applied
Bogdan Nica
Summary: This study investigates the relationship between the independence number and chromatic number in a graph of non-singular matrices over a finite field, and obtains an upper bound for the former and a lower bound for the latter.
LINEAR ALGEBRA AND ITS APPLICATIONS
(2024)
Article
Mathematics, Applied
Dijian Wang, Yaoping Hou, Deqiong Li
Summary: In this paper, a Turán-like problem in signed graphs is studied. The properties of signed graphs are proven in the context of the problem.
LINEAR ALGEBRA AND ITS APPLICATIONS
(2024)
Article
Mathematics, Applied
Tyler Chen, Thomas Trogdon
Summary: This study focuses on the stability of the Lanczos algorithm when applied to problems with eigenvector empirical spectral distribution close to a reference measure characterized by well-behaved orthogonal polynomials. The analysis reveals that the Lanczos algorithm is forward stable on many large random matrix models, even in finite precision arithmetic, which indicates that random matrices differ significantly from general matrices and caution must be exercised when using them to test numerical algorithms.
LINEAR ALGEBRA AND ITS APPLICATIONS
(2024)
Article
Mathematics, Applied
Constantin Costara
Summary: This passage discusses linear mappings on matrices and the relationship between subsets of the spectrum, providing corresponding characterization conditions.
LINEAR ALGEBRA AND ITS APPLICATIONS
(2024)
Article
Mathematics, Applied
Amir Hossein Ghodrati, Mohammad Ali Hosseinzadeh
Summary: This paper presents tight upper bounds for all signless Laplacian eigenvalues of a graph with prescribed order and minimum degree, improving upon previously known bounds. Additionally, the relationship between the number of signless Laplacian eigenvalues falling within specific intervals and various graph parameters such as independence, clique, chromatic, edge covering, and matching numbers is explored.
LINEAR ALGEBRA AND ITS APPLICATIONS
(2024)
Article
Mathematics, Applied
Ya-Lei Jin, Jie Zhang, Xiao-Dong Zhang
Summary: This paper investigates the relationship between the spectral radius of a symmetric matrix and its principal submatrices, and uses these relationships to obtain upper bounds of the spectral radius of graphs.
LINEAR ALGEBRA AND ITS APPLICATIONS
(2024)
Article
Mathematics, Applied
Davide Bolognini, Paolo Sentinelli
Summary: We introduce immanant varieties associated with simple characters of a finite group and discuss the features of one-dimensional characters and trivial characters.
LINEAR ALGEBRA AND ITS APPLICATIONS
(2024)
Article
Mathematics, Applied
A. S. Gordienko
Summary: We introduce the concept of a graded group action on a graded algebra, or equivalently, a group action by graded pseudoautomorphisms. We study the properties of groups of graded pseudoautomorphisms and prove several important theorems and conjectures regarding graded algebras with a group action.
LINEAR ALGEBRA AND ITS APPLICATIONS
(2024)
Article
Mathematics, Applied
Jiaqi Gu, Shenghao Feng, Yimin Wei
Summary: We propose a tensor product structure compatible with the hypergraph structure and define the algebraic connectivity of the hypergraph in this product, establishing its relationship with vertex connectivity. We introduce connectivity optimization problems into the hypergraph and solve them using algebraic connectivity. Additionally, we apply the Laplacian eigenmap algorithm to the hypergraph under our tensor product.
LINEAR ALGEBRA AND ITS APPLICATIONS
(2024)
Article
Mathematics, Applied
Samuel Lichtenberg, Abiy Tasissa
Summary: This paper explores a dual basis approach to Classical Multidimensional Scaling (CMDS) and provides explicit formulas for the dual basis vectors. It also characterizes the spectrum of an essential matrix in the dual basis framework. Connections to a related problem in metric nearness are made.
LINEAR ALGEBRA AND ITS APPLICATIONS
(2024)
