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arXiv · 1811.03772

Quantum Information Capsule and Information Delocalization by Entanglement in Multiple-qubit Systems

Koji Yamaguchi·Naoki Watamura·Masahiro Hotta
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Abstract

Where do entangled multiple-qubit systems store information? For information injected into a qubit, this question is nontrivial and interesting since the entanglement delocalizes the information. So far, a common picture is that of a qubit and its purification partner sharing the information quantum mechanically. Here, we introduce a new picture of a single qubit in the correlation space, referred to as quantum information capsule (QIC), confining the information perfectly. This picture is applicable for the entangled multiple-qubit system in an arbitrary state. Unlike the partner picture, in the QIC picture, by swapping the single-body state, leaving other subsystems untouched, the whole information can be retrieved out of the system. After the swapping process, no information remains in the system.

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Koji Yamaguchi, Naoki Watamura, Masahiro Hotta. 2019-01-15. Quantum Information Capsule and Information Delocalization by Entanglement in Multiple-qubit Systems. https://doi.org/10.1016/j.physleta.2019.01.036

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