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In this work, we delve into the dynamic traits of the relative entropy of quantum coherence (REQC) as the quantum system interacts with the different noisy channels, drawing comparisons with entanglement (concurrence). The research results…

Quantum Physics · Physics 2024-03-01 Wen-Yang Sun , A-Min Ding , Juan He , Jiadong Shi , Le Wang , Hui-Fang Xu , Dong Wang , Liu Ye

We use the relative modular operator to define a generalized relative entropy for any convex operator function g on the positive real line satisfying g(1) = 0. We show that these convex operator functions can be partitioned into convex…

Mathematical Physics · Physics 2015-06-26 Andrew Lesniewski , Mary Beth Ruskai

By using the Choi-Jamio{\l}kowski isomorphism, we propose a well-defined coherence measure of quantum channels based on the generalized $\alpha$-$z$-relative R\'{e}nyi entropy. In addition, we present an alternative coherence measure of…

Quantum Physics · Physics 2025-06-13 Jiaorui Fan , Zhaoqi Wu , Shao-Ming Fei

In analogy with its classical counterpart, a noisy quantum channel is characterized by a loss, a quantity that depends on the channel input and the quantum operation performed by the channel. The loss reflects the transmission quality: if…

Quantum Physics · Physics 2011-07-19 Nicolas J. Cerf

Classical messages can be sent via a noisy quantum channel in various ways, corresponding to various choices of signal states of the channel. Previous work by Holevo and by Schumacher and Westmoreland relates the capacity of the channel to…

Quantum Physics · Physics 2007-05-23 Benjamin Schumacher , Michael D. Westmoreland

We prove that the quantum relative entropy decreases monotonically under the application of any positive trace-preserving linear map, for underlying separable Hilbert spaces. This answers in the affirmative a natural question that has been…

Quantum Physics · Physics 2017-04-21 Alexander Müller-Hermes , David Reeb

We show that the minimum output entropy for all single-mode Gaussian channels is additive and is attained for Gaussian inputs. This allows the derivation of the channel capacity for a number of Gaussian channels, including that of the…

Quantum Physics · Physics 2010-01-21 S. Lloyd , V. Giovannetti , L. Maccone , S. Pirandola , R. Garcia-Patron

We present a noncommutative optimal transport framework for quantum channels acting on von Neumann algebras. Our central object is the Lipschitz cost measure, a transportation-inspired quantity that evaluates the minimal cost required to…

Operator Algebras · Mathematics 2025-06-05 Roy Araiza , Marius Junge , Peixue Wu

We study the quantum correlation dynamics of two relativistic particles which is transmitted through one of the Pauli channels $ \sigma_{x}, \sigma_{y},$ and $\sigma_{z}$. We compare sudden death and robustness of entanglement and geometric…

Quantum Physics · Physics 2012-06-12 M. Mahdian , T. Makaremi , Sh. Salimi

Two partial orderings among communication channels, namely, `being degradable into' and `being less noisy than,' are reconsidered in the light of recent results about statistical comparisons of quantum channels. Though our analysis covers…

Quantum Physics · Physics 2016-12-01 Francesco Buscemi

It is observed that the entropy reduction (the information gain in the initial terminology) of an efficient (ideal or pure) quantum measurement coincides with the generalized quantum mutual information of a q-c channel mapping an a priori…

Quantum Physics · Physics 2015-05-20 M. E. Shirokov

By carrying out appropriate continuous quantum measurements with a family of projection operators, a unitary channel can be approximated in an arbitrary precision in the trace norm sense. In particular, the quantum Zeno effect is described…

Mathematical Physics · Physics 2013-12-10 Toru Fuda

There are several inequalities in physics which limit how well we can process physical systems to achieve some intended goal, including the second law of thermodynamics, entropy bounds in quantum information theory, and the uncertainty…

Quantum Physics · Physics 2016-07-19 Francesco Buscemi , Siddhartha Das , Mark M. Wilde

Many important properties of quantum channels are quantified by means of entropic functionals. Characteristics of such a kind are closely related to different representations of a quantum channel. In the Jamio{\l}kowski-Choi representation,…

Quantum Physics · Physics 2013-07-23 Alexey E. Rastegin

Uniform continuity bounds on entropies are generally expressed in terms of a single distance measure between a pair of probability distributions or quantum states, typically, the total variation distance or trace distance. However, if an…

Quantum Physics · Physics 2025-01-09 Michael G. Jabbour , Nilanjana Datta

We argue that a fundamental (conjectured) property of memoryless quantum channels, namely the strong superadditivity, is intimately related to the decreasing property of the quantum relative entropy. Using the latter we first give, for a…

Quantum Physics · Physics 2009-07-09 Grigori G. Amosov , Stefano Mancini

The measurement outcomes of two incompatible observables on a particle can be precisely predicted when it is maximally entangled with a quantum memory, as quantified recently [Nature Phys. 6, 659 (2010)]. We explore the behavior of the…

Quantum Physics · Physics 2012-07-26 Z. Y. Xu , W. L. Yang , M. Feng

Surprisingly often decoherence is due to classical fluctuations of ambient fields and may thus be described in terms of random unitary (RU) dynamics. However, there are decoherence channels where such a representation cannot exist. Based on…

Quantum Physics · Physics 2015-12-09 Julius Kayser , Kimmo Luoma , Walter T. Strunz

Quantum states naturally decay under noise. Many earlier works have quantified and demonstrated lower bounds on the decay rate, showing exponential decay in a wide variety of contexts. Here we study the converse question: are there uniform…

Quantum Physics · Physics 2024-01-01 Nicholas Laracuente , Graeme Smith

A class of lower bounds for the entanglement cost of any quantum state was recently introduced in [arXiv:2111.02438] in the form of entanglement monotones known as the tempered robustness and tempered negativity. Here we extend their…

Quantum Physics · Physics 2023-02-16 Ludovico Lami , Bartosz Regula