Chinese Physics B

Reversion of weak-measured quantum entanglement state*

Shao-Jiang Du, Yonggang Peng, Hairan Feng, Feng Han, Lian-Wu Yang, Yujun Zheng

Published Apr 23, 2020• 7 citations

Abstract

We theoretically study the reversible process of quantum entanglement state by means of weak measurement and corresponding reversible operation. We present a protocol of the reversion operation in two bodies based on the theory of reversion of single photon and then expend it in quantum communication channels. The theoretical results demonstrate that the protocol does not break the information transmission after a weak measurement and a reversible measurement with the subsequent process in the transmission path. It can reverse the perturbed entanglement intensity evolution to its original state. Under the condition of different weak measurement intensity the protocol can reverse the perturbed quantum entanglement system perfectly. In the process we can get the classical information described by information gain from the quantum system through weak measurement operation. On the other hand, in order to realize complete reversibility, the classical information of the quantum entanglement system must obey a limited range we present in this paper in the reverse process.

DOI: 10.1088/1674-1056/ab8c3e

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