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arXiv · 1902.01571

Completely scrambled memory for quantum superposition

Tetsuya Mukai
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Abstract

Although constructing a quantum computation device with multiple qubits is arguably a difficult task, several seconds of coherence time with tens of thousands of quantum particles has been demonstrated with a trapped atomic ensemble. As a practical application, a security-enhanced quantum state memory using atoms has been demonstrated. It was shown that the quantum superposition preserved in an atomic ensemble was scrambled and faithfully descrambled; however, the scrambled phase ambiguity remained at 50 %. To overcome this problem, we propose and demonstrate a scheme that achieves 100 % phase ambiguity without introducing an extra Ramsey interferometer. Moreover, this scheme can be used as a direct application to keep the choice between two values secret without falsification.

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Tetsuya Mukai. 2019-02-05. Completely scrambled memory for quantum superposition. https://doi.org/10.1038/s41598-018-37772-4

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