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It is well known that it is impossible to clone an arbitrary quantum state. However, this inability does not lead directly to no-cloning of quantum coherence. Here, we show that it is impossible to clone the coherence of an arbitrary…

Quantum state elimination measurements tell us what states a quantum system does not have. This is different from state discrimination, where one tries to determine what the state of a quantum system is, rather than what it is not. Apart…

Motivated by recent experiments [Pashkin et al. Nature, \textbf{421}, 823 (2003)] which showed coherent oscillations of two superconducting qubits system, we consider a system of two charge qubits coupled to a common stripline microwave…

Quantum Physics · Physics 2009-11-13 Nasser Metwally , Mahamoud Abde-Aty

In this paper, we study the entanglement and quantum discord of the output modes in the unified $1\rightarrow 2$ state-dependent cloning and probabilistic quantum cloning. The tripartite entanglement among the output modes and the quantum…

Quantum Physics · Physics 2015-06-23 Jun Zhang , Shao-xiong Wu , Chang-shui Yu

Quantum state exclusion is the task of identifying at least one state from a known set that was not used in the preparation of a quantum system. A set of quantum states is said to admit state exclusion if there exists a measurement whose…

Quantum Physics · Physics 2026-02-06 Debanjan Roy , Tathagata Gupta , Pratik Ghosal , Samrat Sen , Somshubhro Bandyopadhyay

We study coordination under restricted information, where classical local models fail to implement certain correlated distributions because agents cannot condition on past history. We show that quantum systems overcome this limitation even…

Quantum Physics · Physics 2026-05-08 Faisal Shah Khan

We show that the quantum states generated by universal optimal quantum cloning of a single photon represent an universal set of quantum superpositions resilient to decoherence. We adopt Bures distance as a tool to investigate the…

Quantum Physics · Physics 2015-05-18 N. Spagnolo , F. Sciarrino , F. De Martini

We consider a class of entangled states of a quantum system (S) and a second system (A) where pure states of the former are correlated with mixed states of the latter, and work out the entanglement measure with reference to the nearest…

Quantum Physics · Physics 2008-07-04 Avijit Lahiri , Gautam Ghosh , Sankhasubhra Nag

The present work studies quantum and classical correlations in three qubits and four qubits general Bell states, produced by operating with braid operators on the computational basis of states. The analogies between the general three qubits…

Quantum Physics · Physics 2014-11-12 Yacob Ben-Aryeh

Reversible work extraction from identical quantum systems via collective operations was shown to be possible even without producing entanglement among the sub-parts. Here, we show that implementing such global operations necessarily imply…

Quantum Physics · Physics 2015-03-31 Gian Luca Giorgi , Steve Campbell

Entanglement, one of the central mysteries of quantum mechanics, plays an essential role in numerous applications of quantum information theory. A natural question of both theoretical and experimental importance is whether universal…

The non-Markovian decoherence of quantum and classical correlations is analytically obtained when two qubits are asymmetrically subjected to the bit flip channel and phase flip channel. For one class of initial mixed states, quantum…

Quantum Physics · Physics 2012-08-09 Xiang Hao , Tao Pan , Jinqiao Sha

We quantify correlations (quantum and/or classical) between two continuous variable modes in terms of how many correlated bits can be extracted by measuring the sign of two local quadratures. On Gaussian states, such `bit quadrature…

Quantum Physics · Physics 2008-03-24 C. Rodó , Gerardo Adesso , A. Sanpera

We study the relative error of the state-dependent N=>L cloning. A copying transformation and dimension of state space are not specified. Only the unitarity of quantum mechanical transformations is used. The proposed approach is based on…

Quantum Physics · Physics 2007-05-23 A. E. Rastegin

The indistinguishability of non-orthogonal pure states lies at the heart of quantum information processing. Although the indistinguishability reflects the impossibility of measuring complementary physical quantities by a single measurement,…

Quantum Physics · Physics 2019-02-13 Seiseki Akibue , Go Kato , Naoki Marumo

Quantum correlation includes quantum entanglement and quantum discord. Both entanglement and discord have a common necessary condition--------quantum coherence or quantum superposition. In this paper, we attempt to give an alternative…

Quantum Physics · Physics 2014-09-23 Chang-shui Yu , Yang Zhang , Haiqing Zhao

A survey of various concepts in quantum information is given, with a main emphasis on the distinguishability of quantum states and quantum correlations. Covered topics include generalized and least square measurements, state discrimination,…

Quantum Physics · Physics 2015-06-22 Dominique Spehner

We propose a protocol where one can exploit dual quantum and classical channels to achieve perfect ``cloning'' and ``orthogonal-complementing'' of an unknown state with a minimal assistance from a state preparer (without revealing what the…

Quantum Physics · Physics 2008-12-18 Arun Kumar Pati

One of the most challenging problems for the realization of a scalable quantum computer is to design a physical device that keeps the error rate for each quantum processing operation low. These errors can originate from the accuracy of…

Quantum Physics · Physics 2022-12-28 Christian Boudreault , Hichem Eleuch , Michael Hilke , Richard MacKenzie

The impossibility of simultaneously cloning non-orthogonal states lies at the foundations of quantum theory. Even when allowing for approximation errors, cloning an arbitrary unknown pure state requires as many initial copies as needed to…

Quantum Physics · Physics 2026-04-17 Nikhil Bansal , Matthias C. Caro , Gaurav Mahajan