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Related papers: Optimal Broadcasting of Mixed States

200 papers

We present a generalization of quantum teleportation that distributes quantum information from a sender's $d$-level particle to $N_o$ particles held by remote receivers via an initially shared multiparticle entangled state. This entangled…

Quantum Physics · Physics 2009-10-31 Mio Murao , Martin B. Plenio , Vlatko Vedral

We study a quantum state transfer between spins interacting with an arbitrary network of spins coupled by uniform XX interactions. It is shown that in such a system under fairly general conditions, we can expect a nearly perfect transfer of…

Quantum Physics · Physics 2015-06-26 A. Wojcik , T. Luczak , P. Kurzynski , A. Grudka , T. Gdala , M. Bednarska

Interaction with environment may lead to the transition of quantum system from pure state to the mixed one. In this case, the problem of definition of entanglement may arise. In particular, quantitative measure of entanglement concurrence…

Quantum Physics · Physics 2008-09-16 Levan Chotorlishvili

Bounds analogous to entropic uncertainty relations allow one to design practical tests to detect quantum entanglement by a collective measurement performed on several copies of the state analyzed. This approach, initially worked out for…

Quantum Physics · Physics 2013-01-04 Łukasz Rudnicki , Zbigniew Puchała , Paweł Horodecki , Karol Życzkowski

We consider mixed states of two qubits and show under which global unitary operations their entanglement is maximized. This leads to a class of states that is a generalization of the Bell states. Three measures of entanglement are…

Quantum Physics · Physics 2009-11-06 Frank Verstraete , Koenraad Audenaert , Tijl De Bie , Bart De Moor

A fully connected quantum network with a wavelength division multiplexing architecture plays an increasingly pivotal role in quantum information technology. With such architecture, an entanglement-based network has been demonstrated in…

Quantum state purification is the task of recovering a nearly pure copy of an unknown pure quantum state using multiple noisy copies of the state. This basic task has applications to quantum communication over noisy channels and quantum…

Quantum Physics · Physics 2025-01-22 Andrew M. Childs , Honghao Fu , Debbie Leung , Zhi Li , Maris Ozols , Vedang Vyas

We examine the possible states of subsystems of a system of bits or qubits. In the classical case (bits), this means the possible marginal distributions of a probability distribution on a finite number of binary variables; we give necessary…

Quantum Physics · Physics 2015-06-26 Paul Butterley , Anthony Sudbery , Jason Szulc

We establish a connection between optimal quantum cloning and optimal state estimation for d-dimensional quantum systems. In this way we derive an upper limit on the fidelity of state estimation for d-dimensional pure quantum states and,…

Quantum Physics · Physics 2009-10-31 D. Bruss , C. Macchiavello

Quantum broadcasting is central to quantum information processing and characterizes the correlations within quantum states. Nonetheless, traditional quantum broadcasting encounters inherent limitations dictated by the principles of quantum…

Quantum Physics · Physics 2024-07-26 Hongshun Yao , Xia Liu , Chengkai Zhu , Xin Wang

We study the estimation of the overlap between two unknown pure quantum states of a finite dimensional system, given $M$ and $N$ copies of each type. This is a fundamental primitive in quantum information processing that is commonly…

We report the successful generation of an entangled multiparticle quantum superposition of pure photon states. They result from a multiple (universal} cloning of a single photon qubit by a high gain, quantum-injected parametric amplifier.…

Quantum Physics · Physics 2007-05-23 Francesco De Martini , Fabio Sciarrino

While the no-cloning theorem, which forbids the perfect copying of quantum states, is well-known as one of the defining features of quantum mechanics, the question of how well the theory allows a state to be cloned is yet to be completely…

Quantum Physics · Physics 2013-09-25 Alastair Kay , Ravishankar Ramanathan , Dagomir Kaszlikowski

We provide a number of schemes for the splitting up of quantum information among $k$ parties using a $N$-qubit linear cluster state as a quantum channel, such that the original information can be reconstructed only if all the parties…

Quantum Physics · Physics 2010-10-13 Sreraman Muralidharan , Sakshi Jain , Prasanta K. Panigrahi

Reliable methods for the classification and quantification of quantum entanglement are fundamental to understanding its exploitation in quantum technologies. One such method, known as Separable Neural Network Quantum States (SNNS), employs…

Quantum Physics · Physics 2021-06-15 Cillian Harney , Mauro Paternostro , Stefano Pirandola

The relative error of cloning of quantum states with arbitrary prior probabilities is considered. It is assumed that the ancilla may contain some a priori information about the input state to be cloned. The lower bound on the relative error…

Quantum Physics · Physics 2010-06-18 Alexey E. Rastegin

In this work, we exhaustively investigate $1 \rightarrow 2$ local and nonlocal broadcasting of entanglement as well as correlations beyond entanglement (geometric discord) using asymmetric Pauli cloners with most general two qubit state as…

Quantum Physics · Physics 2019-02-20 Aditya Jain , Indranil Chakrabarty , Sourav Chatterjee

We construct the unique optimal quantum device for turning a finite number of d-level quantum systems in the same unknown pure state \sigma into M systems of the same kind, in an approximation of the M-fold tensor product of the state…

Quantum Physics · Physics 2009-10-31 R. F. Werner

We first present a generalized criterion for maximally entangled states of 2, 3, 4, 5, 6, 8 and in theory to arbitrary-number qubits. By this criterion, some known highly entangled multi-qubit states are examined and a new genuine…

Quantum Physics · Physics 2015-06-04 Xinwei Zha , Chenzhi Yuan , Yanpeng Zhang

The Measurement Based Quantum Computation (MBQC) model achieves universal quantum computation by employing projective single qubit measurements with classical feedforward on a highly entangled multipartite cluster state. Rapid advances in…

Quantum Physics · Physics 2021-12-23 Swapnil Nitin Shah