Quantum secure direct communication with quantum memory

Quantum communication provides an absolute security advantage, and it has been widelydeveloped over the past 30 years. As an important branch of quantum communication, quantumsecure direct communication (QSDC) promotes high security and instantaneousness incommunication through directly transmitting messages over a quantum channel. The fullimplementation of a quantum protocol always requires the ability to control the transfer of amessage effectively in the time domain; thus, it is essential to combine QSDC with quantummemory to accomplish the communication task. In this paper, we report the experimentaldemonstration of QSDC with state-of-the-art atomic quantum memory for the first time inprinciple. We used the polarization degrees of freedom of photons as the information carrier, andthe fidelity of entanglement decoding was verified as approximately 90%. Our work completes afundamental step toward practical QSDC and demonstrates a potential application forlong-distance quantum communication in a quantum network.

This article was accepted by Physical Review Letters,

Wei zhang is the first author.

This article was reported by Phys.org

URL: https://phys.org/news/2017-06-physicists-quantum-memory.html