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Related papers: Optimal superbroadcasting of mixed qubit states

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The N to M (M>N) universal quantum broadcasting of mixed states are proposed for qubits system. The broadcasting of mixed states is universal and optimal in the sense that the shrinking factor is independent of input state and achieves the…

Quantum Physics · Physics 2009-11-13 Gui-Fang Dang , Heng Fan

We derive the optimal universal broadcasting for mixed states of qubits. We show that the nobroadcasting theorem cannot be generalized to more than a single input copy. Moreover, for four or more input copies it is even possible to purify…

Quantum Physics · Physics 2007-05-23 Giacomo Mauro D'Ariano , Chiara Macchiavello , Paolo Perinotti

Quantum coherence (QCh) is considered to be a key ingredient in quantum resource theories and also plays a pivotal role in the design and implementation of various information processing tasks. Consequently, it becomes important for us to…

Quantum Physics · Physics 2017-11-22 Indranil Chakrabarty , Udit Kamal Sharma , Manish Kumar Shukla

We address the problem of broadcasting N copies of a generic qubit state to M>N copies by estimating its direction and preparing a suitable output state according to the outcome of the estimate. This semiclassical broadcasting protocol is…

Quantum Physics · Physics 2007-05-23 G. Chiribella , G. M. D'Ariano , C. Macchiavello , P. Perinotti , F. Buscemi

We show that, given a general mixed state for a quantum system, there are no physical means for {\it broadcasting\/} that state onto two separate quantum systems, even when the state need only be reproduced marginally on the separate…

Quantum Physics · Physics 2009-10-28 H. Barnum , C. M. Caves , C. A. Fuchs , R. Jozsa , B. Schumacher

We describe a general framework to study covariant symmetric broadcasting maps for mixed qubit states. We explicitly derive the optimal N to M superbroadcasting maps, achieving optimal purification of the single-site output copy, in both…

Quantum Physics · Physics 2007-05-23 Francesco Buscemi , Giacomo Mauro D'Ariano , Chiara Macchiavello , Paolo Perinotti

The quantum no-broadcasting theorem states that it is impossible to produce perfect copies of an arbitrary quantum state, even if the copies are allowed to be correlated. Here we show that, although quantum broadcasting cannot be achieved…

Quantum Physics · Physics 2024-03-26 Arthur J. Parzygnat , James Fullwood , Francesco Buscemi , Giulio Chiribella

Quantum mechanical properties like entanglement, discord and coherence act as fundamental resources in various quantum information processing tasks. Consequently, generating more resources from a few, typically termed as broadcasting is a…

Quantum Physics · Physics 2019-10-23 Rounak Mundra , Dhrumil Patel , Indranil Chakrabarty , Nirman Ganguly , Sourav Chatterjee

In this work, we extensively study the problem of broadcasting of quantum correlations. This includes broadcasting of quantum entanglement as well as correlations that go beyond the notion of entanglement. It is quite well known from the…

Quantum Physics · Physics 2016-04-13 Sourav Chatterjee , Sk Sazim , Indranil Chakrabarty

While exact cloning of an unknown quantum state is prohibited by the linearity of quantum mechanics, approximate cloning is possible and has been used, e.g., to derive limits on the security of quantum communication protocols. In the case…

Quantum Physics · Physics 2009-11-13 Hongwei Chen , Xianyi Zhou , Dieter Suter , Jiangfeng Du

We prove new quantitative limitations on any approximate simultaneous cloning or broadcasting of mixed states. The results are based on information-theoretic (entropic) considerations and generalize the well known no-cloning and…

Quantum Physics · Physics 2017-07-12 Marius Lemm , Mark M. Wilde

The no-quantum broadcasting theorem which is a weaker version of the nocloning theorem restricts us from broadcasting completely unknown quantum information to multiple users. However, if the sender is aware of the quantum information…

Quantum Physics · Physics 2023-05-02 Satish Kumar , Anirban Pathak

The no-broadcasting theorem, a fundamental limitation on the communication of quantum information, holds that a physical process cannot broadcast copies of an unknown quantum state to two or more receivers. Recent work has explored ways of…

Quantum Physics · Physics 2026-03-23 Matthew Simon Tan , Davit Aghamalyan , Varun Narasimhachar

Quantum cloning of two identical mixed qubits $\rho \otimes \rho $ is studied. We propose the quantum cloning transformations not only for the triplet (symmetric) states but also for the singlet (antisymmetric) state. We can copy these two…

Quantum Physics · Physics 2007-07-12 H. Fan , B. Y. Liu , K. J. Shi

It is well known that quantum theory forbids the exact copying of an unknown quantum state. Therefore in broadcasting of classical information by a quantum channel an additional contribution to the error in the decoding is expected. We…

Quantum Physics · Physics 2007-05-23 A. E. Allahverdyan , D. B. Saakian

Quantum information, though not precisely defined, is a fundamental concept of quantum information theory which predicts many fascinating phenomena and provides new physical resources. A basic problem is to recognize the features of quantum…

Quantum Physics · Physics 2007-06-13 M. Horodecki , P. Horodecki , R. Horodecki , M. Piani

It is well known that classical information can be cloned, but non-orthogonal quantum states cannot be cloned, and non-commuting quantum states cannot be broadcast. We conceive a scenario in which the object we want to broadcast is the…

Quantum Physics · Physics 2013-05-20 Xiao-Ming Lu , Zhe Sun , Xiaoguang Wang , Shunlong Luo , C. H. Oh

Quantum mechanics put restriction on performing some task which we can do classically. One such restriction is that we cannot copy an arbitrary quantum state. This is known as No-cloning theorem. Although quantum mechanics forbid us to…

Quantum Physics · Physics 2009-02-11 Satyabrata Adhikari

We consider the problem of broadcasting quantum information encoded in the average value of the field from N to M>N copies of mixed states of radiation modes. We derive the broadcasting map that preserves the complex amplitude, while…

Quantum Physics · Physics 2007-05-23 Giacomo M. D'Ariano , Paolo Perinotti , Massimiliano F. Sacchi

We consider the hypothetical quantum network case where Alice wishes to transmit one qubit of information (specifically a pure quantum state) to $M$ parties, where $M$ is some large number. The remote receivers locally perform single qubit…

Quantum Physics · Physics 2025-09-16 Elijah Pelofske
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