首页/论文/quant-ph/0601181

arXiv quant-ph/06011812006-01quant-ph

Broadcasting of Inseparability

Satyabrata Adhikari, B. S. Choudhury, Indranil Chakrabarty

备注：: 13 pages, 2 tables, Accepted in Journal of Physics A
发表信息：: J. Phys. A: Math. Gen. 39 No 26 8439-8449 (2006)
DOI：: 10.1088/0305-4470/39/26/011

英文摘要：

Suppose we are given an entangled pair and then one can ask how well we can produce two entangled pairs starting from a given entangled pair using only local operations. To give response of the above asked question, we study broadcasting of entanglement using state dependent quantum cloning machine as a local copier. We show that the length of the interval for probability-amplitude-squared for broadcasting of entanglement using state dependent cloner can be made larger than the length of the interval for probability-amplitude-squared for broadcasting entanglement using state independent cloner. Further we show that there exists local state dependent cloner which gives better quality copy (in terms of average fidelity) of an entangled pair than the local universal cloner.

机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。

阅读原文

阅读 PDF ↗

arXiv 页面 ↗HTML 原文 ↗

本文内容

英文摘要相关论文

机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。

继续探索

相关论文

Broadcasting of entanglement and universal quantum cloners

We study broadcasting of entanglement where we use universal quantum cloners (in general less optimal) to perform local cloning operations. We show that there is a lower bound on the fidelity of the universal quantum cloners that can be used for broadcasting. We prove that an entanglement is optimally broadcast only when optimal quantum cloners are used for local copying. We also show that broadcasting of entanglement into more than two entangled pairs is forbidden using only local operations.

1999-06-02quant-ph

Is an optimal quantum cloner the best choice for local copying in broadcasting entanglement?

The paper is temporarily withdrawn by the authors.

1999-01-06quant-ph

State Dependent and Independent cloner: Cloning and Broadcasting

In this work, we extensively study the problem of broadcasting of entanglement. In the first part of the work, we reconceptualize the idea of state dependent quantum cloning machine, and in that process we introduce different types of state dependent cloners like static and dynamic state dependent cloners. We derive the conditions under which we can make these cloners independent of the input state. In the broadcasting part, as our resource initial state, we start with general two qubit state and consider specific examples like, non maximally entangled state (NME), Werner like state (WS), and …

2019-03-25quant-ph

Broadcasting of correlations via orthogonal & non-orthogonal state dependent cloners

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 process, we introduce different types of SD-QCMs, namely, orthogonal and non-orthogonal cloners. We derive the conditions for which the fidelity of these cloners will become independent of the input state. We note that such a construction allows us to maximize the cloning fidelity at the cost of having partial information of the input state. In the discussion o…

2019-12-05quant-ph

Asymmetric broadcasting of quantum correlations

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 the resource. We exemplify asymmetric broadcasting of entanglement using Maximally Entangled Mixed States. We demonstrate the variation of broadcasting range with the amount of entanglement present in the resource state as well as with the asymmetry in the cloner. We show that it is impossible to optimally broadcast geometric discord with the help of these a…

2019-01-11quant-ph

实验性虚拟量子广播

Experimental Virtual Quantum Broadcasting

本研究在核磁共振系统中实验实现了虚拟量子广播，通过线性组合酉算子电路结合后处理协议，利用通用克隆器和反对称器实现接近理想的广播保真度，适用于任意维度量子系统。

2025-06-24quant-ph

更多相关论文收起更多论文

Broadcasting of Quantum Correlations: Possibilities & Impossibilities

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 "No-Broadcasting theorem" that perfect broadcasting of quantum correlation is not possible. However it does not rule out the possibility of partial broadcasting of correlations where we can get lesser correlated states from a given correlated state. In order to have a holistic view of broadcasting, we investigate this problem by starting with most general repr…

2016-02-22quant-ph

Quantum Cloning of Continuous Variable Entangled States

We consider the quantum cloning of continuous variable entangled states. This is achieved by introducing two symmetric entanglement cloning machines (or e-cloners): a local e-cloner and a global e-cloner; where we look at the preservation of entanglement in the clones under the condition that the fidelity of the clones is maximized. These cloning machines are implemented using simple linear optical elements such as beam splitters and homodyne detection along with squeeze gates. We show that the global e-cloner out-performs the local e-cloner both in terms of the fidelity of the cloned states a…

2007-11-01quant-ph

Disentangling and broadcasting an entangled state simultaneously by asymmetric cloning

We construct a quantum machine which, by using asymmetric cloner, deals with disentangling and broadcasting entanglement in a single unitary evolution. The attainable maximum value of the scaling parameter $s$ for disentangling is identical to that obtained in previous works. The fidelity of the cloning state with respect to the input entangled state is state-dependent.

2002-10-06quant-ph

Broadcasting of entanglement via local copying

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 entangled states using only local operations. This procedure can be viewed as an inversion of quantum purification procedures.

1997-01-23quant-ph

Broadcasting of three qubit entanglement via local copying and entanglement swapping

In this work,We investigate the problem of secretly broadcasting of three-qubit entangled state between two distant partners. The interesting feature of this problem is that starting from two particle entangled state shared between two distant partners we find that the action of local cloner on the qubits and the measurement on the machine state vector generates three-qubit entanglement between them. The broadcasting of entanglement is made secret by sending the measurement result secretly using cryptographic scheme based on orthogonal states. Further we show that this idea can be extended to …

2006-07-11quant-ph

非定域性的广播

Broadcasting of non-locality

本文利用通用Buzek-Hillary局域量子克隆机研究非定域性的广播，证明在Bell-CHSH、CJWR导引及Svetlichny不等式框架下，两量子比特和三量子比特系统的非定域性及导引性均无法通过局域克隆广播。

2024-04-24quant-ph

Two-qubit universal and state-dependent quantum cloning machine and quantum correlation broadcasting

Due to the axioms of quantum mechanics, perfect cloning of an unknown quantum state is impossible. But since imperfect cloning is still possible, a question arises: "Is there an optimal quantum cloning machine?" Buzek and Hillery answer to this question and construct their famous B-H quantum cloning machine. The B-H machine clones state of an arbitrary single qubit in optimal manner and hence it is universal. Generalizing this machine for two-qubit system is straightforward, but this procedure does not preserve quantum correlation existing in bipartite state in optimal manner and also, during …

2016-04-18quant-ph