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Related papers: Von Neumann entropy from unitarity

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In this work, we use the theory of quantum states over time to define an entropy $S(\rho,\mathcal{E})$ associated with quantum processes $(\rho,\mathcal{E})$, where $\rho$ is a state and $\mathcal{E}$ is a quantum channel responsible for…

Quantum Physics · Physics 2023-07-24 James Fullwood , Arthur J. Parzygnat

Studying the typical entanglement entropy of a bipartite system when averaging over different ensembles of pure quantum states has been instrumental in different areas of physics, ranging from many-body quantum chaos to black hole…

Quantum Physics · Physics 2025-07-08 Lucas Hackl , Mario Kieburg , Joel Maldonado

In this work we investigate the conditions for quantum back action to result in a phase transition in the information dynamics of a monitored system. We introduce a framework that captures a wide range of experiments encompassing probes…

Quantum Physics · Physics 2025-01-20 Shane P. Kelly , Jamir Marino

Quantum mechanical entanglement is a resource for quantum computation, quantum teleportation, and quantum cryptography. The ability to quantify this resource correctly has thus become of great interest to those working in the field of…

Quantum Physics · Physics 2009-11-07 J. R. Gittings , A. J. Fisher

If the von Neumann equation is modified by time dependent statistical weights, the time rate of entropy, the entropy exchange and production of a Schottky system are derived whose Hamiltonian does not contain the interaction with the…

Quantum Physics · Physics 2019-01-30 Wolfgang Muschik

We present a theory of the entanglement transition tuned by measurement strength in qudit chains evolved by random unitary circuits and subject to either weak or random projective measurements. The transition can be understood as a…

Statistical Mechanics · Physics 2020-03-05 Yimu Bao , Soonwon Choi , Ehud Altman

We study the behavior of bipartite entanglement at fixed von Neumann entropy. We look at the distribution of the entanglement spectrum, that is the eigenvalues of the reduced density matrix of a quantum system in a pure state. We report the…

Quantum Physics · Physics 2013-05-29 Paolo Facchi , Giuseppe Florio , Giorgio Parisi , Saverio Pascazio , Kazuya Yuasa

Quantum entropy is an important measure for describing the uncertainty of a quantum state, more uncertainty in subsystems implies stronger quantum entanglement between subsystems. Our goal in this work is to quantify bipartite entanglement…

Quantum Physics · Physics 2022-04-18 Xue Yang , Yan-Han Yang , Li-Ming Zhao , Ming-Xing Luo

We study the entanglement in a system consisting of two non-interacting atoms located in separate cavities, both in their ground states. A single incoming photon has a non-zero probability of entering either of the two cavities. The…

Quantum Physics · Physics 2017-04-25 Samina S. Masood , Allen Miller

The entanglement entropy (von Neumann entropy) has been used to characterize the complexity of many-body ground states in strongly correlated systems. In this paper, we try to establish a connection between the lower bound of the von…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 S. Ryu , Y. Hatsugai

We show that the rate of increase of von Neumann entropy computed from the reduced density matrix of an open quantum system is an excellent indicator of the dynamical behavior of its classical hamiltonian counterpart. In decohering quantum…

Quantum Physics · Physics 2015-06-26 W. H. Zurek , J. P. Paz

Entropy is one of the central quantities in thermodynamics, whose flow between two systems determines the statistics of energy transfers. In quantum systems entropy is non-linear in density matrix whose time evolution is cumbersome. Using…

Mesoscale and Nanoscale Physics · Physics 2019-12-06 Mohammad H. Ansari

Based on the recently introduced averaging procedure in phase space, a new type of entropy is defined on the von Neumann lattice. This quantity can be interpreted as a measure of uncertainty associated with simultaneous measurement of the…

Quantum Physics · Physics 2009-11-07 Sumiyoshi Abe , J. Zak

In this paper we consider a system of two two-level atoms interacting with a single-mode quantized electromagnetic field in a lossless resonant cavity via $l$-photon-transition mechanism. The field and the atoms are initially prepared in…

Quantum Physics · Physics 2009-11-13 Faisal A. A. El-Orany , Wahiddin M R B , Obada A-S F

We derive the strong subadditivity of the von Neumann entropy with a strict lower bound dependent on the distribution of quantum correlation in the system. We investigate the structure of states saturating the bounded subadditivity and…

Quantum Physics · Physics 2022-05-26 L. R. S. Mendes , M. C. de Oliveira

The single qubit quantum teleportation (sender and receiver are Alice and Bob respectively) is analyzed from the aspect of the quantum information theories. The various quantum entropies are computed at each stage, which ensures the…

We consider information characteristics of single qudit state (spin j=9/2), such as von Neumann entropy, von Neumann mutual information. We review different mathematical properties of these information characteristics: subadditivity and…

Quantum Physics · Physics 2018-07-03 V. I. Manko , T. Sabyrgaliyev

In this article, we present quantum algorithms for estimating von Neumann entropy and Renyi entropy, which are crucial physical and information-theoretical properties of a given quantum state $\rho$. Although there have been existing works…

Quantum Physics · Physics 2025-02-12 Nhat A. Nghiem , Tzu-Chieh Wei

We introduce a task that we call partial decoupling, in which a bipartite quantum state is transformed by a unitary operation on one of the two subsystems and then is subject to the action of a quantum channel. We assume that the subsystem…

Quantum Physics · Physics 2021-10-20 Eyuri Wakakuwa , Yoshifumi Nakata

We study the von Neumann entropy of the partial trace of a system of two two-level atoms (qubits) in a dispersive cavity where the atoms are interacting collectively with a single mode electromagnetic field in the cavity. We make a contrast…

Quantum Physics · Physics 2021-10-01 Ram Narayan Deb