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We study systematically resource measures of coherence and entanglement based on R\'enyi relative entropies, which include the logarithmic robustness of coherence, geometric coherence, and conventional relative entropy of coherence together…

Quantum Physics · Physics 2017-11-29 Huangjun Zhu , Masahito Hayashi , Lin Chen

Entanglement is the key resource for quantum technologies and is at the root of exciting many-body phenomena. However, quantifying the entanglement between two parts of a real-world quantum system is challenging when it interacts with its…

Quantum Physics · Physics 2023-03-22 Christian Carisch , Oded Zilberberg

The many-body localised phase of quantum systems is an unusual dynamical phase wherein the system fails to thermalise and yet, entanglement grows unboundedly albeit very slowly in time. We present a microscopic theory of this ultraslow…

Disordered Systems and Neural Networks · Physics 2024-12-23 Bikram Pain , Sthitadhi Roy

Entanglement and coherence are fundamental properties of quantum systems, promising to power near future quantum technologies, such as quantum computation, quantum communication and quantum metrology. Yet, their quantification, rather than…

We report the creation of a wide range of quantum states with controllable degrees of entanglement and entropy using an optical two-qubit source based on spontaneous parametric downconversion. The states are characterised using measures of…

Quantum Physics · Physics 2009-11-07 A. G. White , D. F. V. James , W. J. Munro , P. G. Kwiat

Quantum information scrambling (QIS) is a characteristic feature of several quantum systems, ranging from black holes to quantum communication networks. While accurately quantifying QIS is crucial to understanding many such phenomena,…

We show that the entanglement between the internal (spin) and external (position) degrees of freedom of a qubit in a random (dynamically disordered) one-dimensional discrete time quantum random walk (QRW) achieves its maximal possible value…

Quantum Physics · Physics 2013-11-04 Rafael Vieira , Edgard P. M. Amorim , Gustavo Rigolin

It is a fundamental problem how the universal concept of classical chaos emerges from the microscopic description of quantum mechanics. We here study standard classical chaos in a framework of quantum mechanics. In particular, we design a…

Quantum Physics · Physics 2023-09-26 Taiki Haga , Shin-ichi Sasa

The complexity of simulating quantum many-body dynamics, or quantum computations, in the Heisenberg picture is governed by the scrambling of initially simple operators into superpositions of exponentially many Pauli strings. The…

Quantum Physics · Physics 2026-05-20 Neil Dowling , Xhek Turkeshi , Jacopo De Nardis , Guglielmo Lami

The entanglement between two arbitrary subsystems of random pure states is studied via properties of the density matrix's partial transpose, $\rho_{12}^{T_2}$. The density of states of $\rho_{12}^{T_2}$ is close to the semicircle law when…

Quantum Physics · Physics 2018-07-23 Udaysinh T. Bhosale , Steven Tomsovic , Arul Lakshminarayan

Entanglement is a key resource for quantum information technologies ranging from quantum sensing to quantum computing. Conventionally, the entanglement between two coupled qubits is established at the time scale of the inverse of the…

Quantum Physics · Physics 2023-09-12 Zeng-Zhao Li , Weijian Chen , Maryam Abbasi , Kater W. Murch , K. Birgitta Whaley

Most experimental protocols for measuring scrambling require time evolution with a Hamiltonian and with the Hamiltonian's negative counterpart (backwards time evolution). Engineering controllable quantum many-body systems for which such…

Quantum Physics · Physics 2018-06-20 Brian Swingle , Nicole Yunger Halpern

We present universal relations between entanglement entropy, which quantifies the quantum correlation between subsystems, and the elastic cross section, which is the primary observable for high energy particle scattering, by employing a…

High Energy Physics - Theory · Physics 2024-10-31 Ian Low , Zhewei Yin

We investigate the scaling of the R\'enyi $\alpha$-entropies in one-dimensional gapped quantum spin models. We show that the block entropies with $\alpha > 2$ violate the area law monotonicity and exhibit damped oscillations. Depending on…

Strongly Correlated Electrons · Physics 2012-08-06 S. M. Giampaolo , S. Montangero , F. Dell'Anno , S. De Siena , F. Illuminati

The evolution of entanglement entropy in quantum circuits composed of Haar-random gates and projective measurements shows versatile behavior, with connections to phase transitions and complexity theory. We reformulate the problem in terms…

Disordered Systems and Neural Networks · Physics 2020-04-16 Oles Shtanko , Yaroslav A. Kharkov , Luis Pedro García-Pintos , Alexey V. Gorshkov

The concept of entanglement entropy appears in multiple contexts, from black hole physics to quantum information theory, where it measures the entanglement of quantum states. We investigate the entanglement entropy in a simple model, the…

Mesoscale and Nanoscale Physics · Physics 2015-05-13 Karyn Le Hur

We introduce a generalization of entanglement based on the idea that entanglement is relative to a distinguished subspace of observables rather than a distinguished subsystem decomposition. A pure quantum state is entangled relative to such…

Quantum Physics · Physics 2009-11-10 Howard Barnum , Emanuel Knill , Gerardo Ortiz , Rolando Somma , Lorenza Viola

One of the greatest challenges in quantum information processing is the coherent control over quantum systems with an ever increasing number of particles. Within this endeavor, the harnessing of many-body entanglement against the effects of…

Quantum Physics · Physics 2015-04-03 Leandro Aolita , Fernando de Melo , Luiz Davidovich

Entanglement distribution is key to the success of secure communication schemes based on quantum mechanics, and there is a strong need for an ultimate architecture able to overcome the limitations of recent proposals such as those based on…

Quantum Physics · Physics 2015-09-10 Alexander Streltsov , Remigiusz Augusiak , Maciej Demianowicz , Maciej Lewenstein

A possible solution of the information paradox can be sought in quantum information scrambling. In this paradigm, it is postulated that all information entering a black hole is rapidly and chaotically distributed across the event horizon…

Quantum Physics · Physics 2021-01-20 Akram Touil , Sebastian Deffner