Source-linked AI summary
Quantum Secure Direct Communication with Quantum Memory
Wei Zhang, Dong-Sheng Ding, Yu-Bo Sheng, Lan Zhou, Bao-Sen Shi, Guang-Can Guo
TL;DR
QSDC requires time-domain control of message transfer, motivating its combination with quantum memory. This paper experimentally demonstrates QSDC using genuine atomic quantum memory and reports approximately 90% entanglement-decoding fidelity.
Problem
Implementing QSDC requires effective time-domain control of message transfer, but proof-of-principle demonstrations have lacked the quantum memory needed for practical application.
Method
The paper demonstrates QSDC experimentally using genuine atomic quantum memory and polarization-encoded photons with prearranged entangled pairs.
Results
Approximately 90% entanglement-decoding fidelity was achieved in the QSDC experiment.
Takeaways & Limitations
The demonstration constitutes a key advance toward practical QSDC and a potential application for long-distance quantum communication in a quantum network.
Takeaways & Limitations
The work is a proof-of-principle demonstration, so practical application remains beyond the demonstrated scope.
Abstract
from arXiv · showhide
Quantum communication provides an absolute security advantage, and it has been widely developed over the past 30 years. As an important branch of quantum communication, quantum secure direct communication (QSDC) promotes high security and instantaneousness in communication through directly transmitting messages over a quantum channel. The full implementation of a quantum protocol always requires the ability to control the transfer of a message effectively in the time domain; thus, it is essential to combine QSDC with quantum memory to accomplish the communication task. In this paper, we report the experimental demonstration of QSDC with state-of-the-art atomic quantum memory for the first time in principle. We used the polarization degrees of freedom of photons as the information carrier, and the fidelity of entanglement decoding was verified as approximately 90%. Our work completes a fundamental step toward practical QSDC and demonstrates a potential application for long-distance quantum communication in a quantum network.