Completely scrambled memory for quantum superposition
arXiv:1902.01571 · doi:10.1038/s41598-018-37772-4
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.
6 pages, 3 figures, 1 table