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arXiv · 1902.05675

Quantum Information Capsule in Multiple-Qudit Systems and Continuous-Variable Systems

Koji Yamaguchi·Masahiro Hotta
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Abstract

Quantum correlations in an entangled many-body system are capable of storing information. Even when the information is injected by a local unitary operation to the system, the entanglement delocalizes it. In a recent study on multiple-qubit systems, it is shown that a virtual qubit defined in the correlation space plays a role of perfect storage of delocalized information, which is called a quantum information capsule (QIC). In order to enhance the capacity of quantum information storage, it is crucial to formulate the cases for multiple-qudit systems and continuous-variable (CV) systems. We analytically prove that it is possible to construct a QIC for general write operations of the systems. It turns out that the extension to quantum field theory is achievable. For Gaussian states, we explicitly construct a QIC for shift write operations. We analyze the time-evolution of QIC in a CV system to demonstrate the diffusion of information in entangled pure states.

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Koji Yamaguchi, Masahiro Hotta. 2019-04-16. Quantum Information Capsule in Multiple-Qudit Systems and Continuous-Variable Systems. https://doi.org/10.1016/j.physleta.2020.126447

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