Dharmaraj Ramachandran, Aditya Dubey, Subrahmanyam S. G. Mantha, Radhika Vathsan
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引用次数: 0
Abstract
We introduce an entanglement measure, the Modified Bloch Norm (MBN), for finite-dimensional bipartite mixed states, based on the improved Bloch matrix criteria (Shen et al. in Sci. Rep. 6:1, 2016). MBN is demonstrated to be effective in analyzing the dynamics of bound entanglement-a valuable resource for quantum protocols where free entanglement may not be available. Through examples, we illustrate the applications of MBN in accurately estimating the Entanglement Sudden Death (ESD) time and detecting behavior such as the freezing of entanglement. Additionally, we show that the error rate for entanglement measured using state estimation from a limited number of measurement copies is significantly lower when using MBN compared to negativity. This demonstrates the robustness of MBN under practical constraints.
基于改进的Bloch矩阵准则(Shen et al. in Sci.),我们为有限维二部混合态引入了一种纠缠度量,即修正Bloch范数(MBN)。众议员6:1,2016)。MBN在分析束缚纠缠动力学方面被证明是有效的,这是一个有价值的资源,对于无法获得自由纠缠的量子协议来说。通过实例说明了MBN在准确估计纠缠猝死(ESD)时间和检测纠缠冻结等行为方面的应用。此外,我们表明,使用有限数量的测量副本的状态估计来测量纠缠的错误率在使用MBN时明显低于使用负性。这证明了MBN在实际约束下的鲁棒性。
期刊介绍:
Quantum Information Processing is a high-impact, international journal publishing cutting-edge experimental and theoretical research in all areas of Quantum Information Science. Topics of interest include quantum cryptography and communications, entanglement and discord, quantum algorithms, quantum error correction and fault tolerance, quantum computer science, quantum imaging and sensing, and experimental platforms for quantum information. Quantum Information Processing supports and inspires research by providing a comprehensive peer review process, and broadcasting high quality results in a range of formats. These include original papers, letters, broadly focused perspectives, comprehensive review articles, book reviews, and special topical issues. The journal is particularly interested in papers detailing and demonstrating quantum information protocols for cryptography, communications, computation, and sensing.