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arXiv · 1105.5258

No-compressing of quantum phase information

Yi-Nan Wang·Han-Duo Shi·Li Jing·Zhao-Xi Xiong·Jin Lei·Liang-Zhu Mu·Heng Fan
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Abstract

We raise a general question of quantum information theory whether the quantum phase information can be compressed and retrieved. A general qubit contains both amplitude and phase information, while an equatorial qubit contains only a phase information. We study whether it is possible to compress the phase information of n equatorial qubits into m general qubits with m being less than n, and still those information can be retrieved perfectly. We prove that this process is not allowed by quantum mechanics.

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Yi-Nan Wang, Han-Duo Shi, Li Jing, Zhao-Xi Xiong, Jin Lei, Liang-Zhu Mu, Heng Fan. 2011-12-13. No-compressing of quantum phase information. https://doi.org/10.1088/1751-8113%2F45%2F2%2F025304

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