NTT Basic Research Laboratories, NTT Corporation, 3-1, Morinosato-Wakamiya, Atsugi, Kanagawa, 243-0198, Japan.
Sci Rep. 2017 Jul 27;7(1):6667. doi: 10.1038/s41598-017-07121-y.
Security enhancement is important in terms of both classical and quantum information. The recent development of a quantum storage device is noteworthy, and a coherence time of one second or longer has been demonstrated. On the other hand, although the encryption of a quantum bit or quantum memory has been proposed theoretically, no experiment has yet been carried out. Here we report the demonstration of a quantum memory with an encryption function that is realized by scrambling and retrieving the recorded quantum phase. We developed two independent Ramsey interferometers on an atomic ensemble trapped below a persistent supercurrent atom chip. By operating the two interferometers with random phases, the quantum phase recorded by a pulse of the first interferometer was modulated by the second interferometer pulse. The scrambled quantum phase was restored by employing another pulse of the second interferometer with a specific time delay. This technique paves way for improving the security of quantum information technology.
在经典信息和量子信息领域，安全性的提升都很重要。最近量子存储设备的发展引人注目，已经有研究展示了其超过 1 秒的相干时间。另一方面，尽管量子位或量子存储器的加密在理论上已经被提出，但还没有进行实际实验。在这里，我们报告了一种通过记录量子相位的扰乱和恢复来实现加密功能的量子存储器的演示。我们在一个被持续超导电流原子芯片捕获的原子系综上开发了两个独立的 Ramsey 干涉仪。通过用随机相位操作两个干涉仪，第一个干涉仪的脉冲记录的量子相位被第二个干涉仪脉冲调制。通过用第二个干涉仪的特定时间延迟的另一脉冲，恢复了扰乱的量子相位。该技术为提高量子信息技术的安全性铺平了道路。
