相关论文: Telecloning and multiuser quantum channels for con…

We show that inseparability of quantum states can be partially broadcasted (copied, cloned) with the help of local operations, i.e. distant parties sharing an entangled pair of spin 1/2 states can generate two pairs of partially nonlocally…

Optical telecommunication is at the heart of today's internet and is currently enabled by the transmission of intense optical signals between remote locations. As we look to the future of telecommunication, quantum mechanics promise new…

In this work, we extensively study the problem of broadcasting of entanglement as state dependent versus state independent cloners. We start by re-conceptualizing the idea of state dependent quantum cloning machine (SD-QCM), and in that…

In this article, we find a theorem that gives a relation between the maximal fidelity of teleportation and the concurrence of the inseparable $X$ state used as a quantum channel in this process. Furthermore, we evaluate the concurrence of…

Quantum telecloning is a multiparty quantum communication protocol which allows quantum information broadcasting. It can be, therefore, seen as a generalization of quantum teleportation. However, in contrast to quantum teleportation, it…

Coherent information quantifies the achievable rate of the reliable quantum information transmission through a communication channel. Use of the correlated quantum states instead of the factorized ones may result in an increase in the…

We introduce a repeater scheme to efficiently distribute multipartite entangled states in a quantum network with optimal scaling. The scheme allows to generate graph states such as 2D and 3D cluster states of growing size or GHZ states over…

We establish the best possible approximation to a perfect quantum cloning machine which produces two clones out of a single input. We analyze both universal and state-dependent cloners. The maximal fidelity of cloning is shown to be 5/6 for…

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…

All communication channels are at bottom quantum mechanical. Quantum mechanics contributes both obstacles to communication in the form of noise, and opportunities in the use of intrinsically quantum representations for information. This…

We explicate conditions under which, the two magnon state becomes highly entangled and is useful for several quantum communication protocols. This state, which is experimentally realizable in quantum dots using Heisenberg exchange…

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…

The cloning of quantum variables with continuous spectra is investigated. We define a Gaussian 1-to-2 cloning machine, which copies equally well two conjugate variables such as position and momentum or the two quadrature components of a…

Sharing entanglement across quantum interconnects is fundamental for quantum information processing. We discuss a practical setting where this interconnect, modeled by a quantum channel, is used once with the aim of sharing high fidelity…

The generation of continuous-variable multipartite entangled states is important for several protocols of quantum information processing and communication, such as one-way quantum computation or controlled dense coding. In this article we…

Quantum repeaters (QRs) provide a way of enabling long distance quantum communication by establishing entangled qubits between remote locations. We investigate a new approach to QRs in which quantum information can be faithfully transmitted…

Large-scale fault-tolerant superconducting quantum computation needs rapid quantum communication to network qubits fabricated on different chips and long-range couplers to implement efficient quantum error-correction codes. Quantum channels…

A major challenge of today's quantum communication systems lies in the transmission of quantum information with high rates over long distances in the presence of unavoidable losses. Thereby the achievable quantum communication rate is…

Quantum communication is needed to build powerful quantum computers and establish reliable quantum networks. At its basis lies the ability to generate and distribute entanglement to separate quantum systems, which can be used to run remote…

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…