English
Related papers

Related papers: More entanglement implies higher performance in ta…

200 papers

We present a class of entanglement identifiers which has the following experimentally friendly feature: once the expectation value of the identifier exceeds some definite limit, we can conclude the state is entangled, even if not all…

Quantum Physics · Physics 2013-08-22 Wieslaw Laskowski , Marcin Markiewicz , Tomasz Paterek , Ryszard Weinar

Entangled states that cannot be distilled to maximal entanglement are called bound entangled and they are often viewed as too weak to break the limitations of classical models. Here, we show a strongly contrasting result: that bound…

Quantum Physics · Physics 2026-03-09 Armin Tavakoli , Carles Roch i Carceller , Lucas Tendick , Tamás Vértesi

We introduce a weak form of the realignment separability criterion which is particularly suited to detect continuous-variable entanglement and is physically implementable (it requires linear optics transformations and homodyne detection).…

Quantum Physics · Physics 2021-08-24 Anaelle Hertz , Matthieu Arnhem , Ali Asadian , Nicolas J. Cerf

We introduce and study a class of entanglement criteria based on the idea of applying local contractions to an input multipartite state, and then computing the projective tensor norm of the output. More precisely, we apply to a mixed…

Quantum Physics · Physics 2020-10-14 Maria Anastasia Jivulescu , Cécilia Lancien , Ion Nechita

We solve the problem of discriminating with minimum error probability two given Pauli channels. We show that, differently from the case of discrimination between unitary transformations, the use of entanglement with an ancillary system can…

Quantum Physics · Physics 2009-11-11 Massimiliano F. Sacchi

Separability problem, to decide whether a given state is entangled or not, is a fundamental problem in quantum information theory. We propose a powerful and computationally simple separability criterion, which allows us to detect the…

Quantum Physics · Physics 2009-11-13 Cheng-Jie Zhang , Yong-Sheng Zhang , Shun Zhang , Guang-Can Guo

The ability to efficiently characterize the spatial correlations of entangled states of light is critical for applications of many quantum technologies such as quantum imaging. Here, we demonstrate highly efficient theoretical and…

Quantum Physics · Physics 2024-10-08 Mahtab Amooei , Girish Kulkarni , Jeremy Upham , Robert W. Boyd

By exploiting the permutation symmetry of Dick states, we derive closed analytical expressions of Schmidt decompositions for {\it all} possible bipartitions of a system described by this kind of state. This allows us to exhaustively compute…

Quantum Physics · Physics 2018-01-03 M. G. M. Moreno , Fernando Parisio

We find optimality conditions for testers in discrimination of quantum channels. These conditions are obtained using semidefinite programming and are similar to optimality conditions for POVMs obtained by Holevo for ensembles of quantum…

Quantum Physics · Physics 2017-01-26 Anna Jenčová , Martin Plávala

We study entanglement in a system of three coupled quantum harmonic oscillators. Specifically, we use the Schmidt decomposition to analyze how the entanglement is distributed among the three subsystems. The Schmidt decomposition is a…

Quantum Physics · Physics 2024-09-30 Abdeldjalil Merdaci , Ahmed Jellal

We introduce a set of electric-field based inequalities capable of detecting multilevel entanglement from a system of N quantum emitters. We determine that the polarization channel as well as the direction of detection can enhance…

Quantum Physics · Physics 2026-02-10 Pedro Rosario , Romain Bachelard

In this paper, the following scenario is considered: there are two qubits possessed by two parties at different locations. Qubits have been prepared in one of a maximum of four, mutually-orthogonal, entangled states and the parties wish to…

Quantum Physics · Physics 2016-09-29 Özenç Güngör , Sadi Turgut

An asymptotic entanglement measure for any bipartite states is derived in the light of the dense coding capacity optimized with respect to local quantum operations and classical communications. General properties and some examples with…

Quantum Physics · Physics 2015-06-26 Tohya Hiroshima

The relation between the violation of the Bell-CHSH inequalities and entanglement properties of quantum states is not clear so one may consider the mixedness of the system to understand the entanglement properties better than the Bell-CHSH…

Quantum Physics · Physics 2009-06-11 Satyabrata Adhikari

We study two complementary diagnostics of bipartite quantum channels, namely fidelity preservation across different classes of input states and entanglement generation from product inputs, given by properly defined entangling power for…

Quantum Physics · Physics 2026-05-27 Marcin Rudziński , Gianluigi Tartaglione , Karol Życzkowski

In this letter we have established the physical character of pure bipartite states with the same amount of entanglement in the same Schmidt rank that either they are local unitarily connected or they are incomparable. There exist infinite…

Quantum Physics · Physics 2008-05-20 Indrani Chattopadhyay , Debasis Sarkar

Entanglement is a central resource in quantum information science, yet its structure in high dimensions remains notoriously difficult to characterize. One of the few general results on high-dimensional entanglement is given by peel-off…

Quantum Physics · Physics 2025-09-10 Robin Krebs , Mariami Gachechiladze

We show that combining randomized measurement protocols with importance sampling allows for characterizing entanglement in significantly larger quantum systems and in a more efficient way than in previous work. A drastic reduction of…

Quantum Physics · Physics 2023-01-26 Aniket Rath , Rick van Bijnen , Andreas Elben , Peter Zoller , Benoît Vermersch

The Schmidt number is of crucial importance in characterizing the bipartite pure states. We explore and propose here a generalization of Schmidt number for states in multipartite systems. It is shown to be entanglement monotonic and valid…

Quantum Physics · Physics 2015-05-12 Yu Guo , Heng Fan

It is shown that while entanglement remains a significant factor in discriminating a set of mutually orthogonal entangled states perfectly by local operations and classical communication (LOCC), entanglement content is not. In particular,…

Quantum Physics · Physics 2010-03-02 Somshubhro Bandyopadhyay