Quantum cryptography has reached another milestone with the success of storing and controlling data in quantum memory. Physicists from University of Science and Technology of China and Nanjing University of Posts and Telecommunications has been able to optimize the Quantum Secure Direct Communication (QSDC) protocol
The research from the two Chinese universities has been published in the Physical Review Letter Journal vol. 118/22. The lead author of the paper titled "Quantum Secure Direct Communication with Quantum Memory" is a Professor of Geophysics from Key Laboratory of Quantum Information at the University of Science and Technology of China, Wei Zhang.
This finding is a breakthrough for improving the Quantum Secure Direct Communication protocol, which until recently still uses the fiber delay lines as the communication channel, instead of quantum memory. The limitation of the quantum cryptography in using fiber lines has made limit the full potential of QSDC for quantum data transfer and storage.
One limitation in the Quantum Secure Direct Communication protocol with conventional data channel was shown by physicists from the Wits University in South Africa. The team of physicists, led by Professor Andrew Forbes, a Distinguished Professor in the School of Physics has shown that secure line communication in quantum data transfer requires a certain degree of error correction, to ensure its reliability.
Quantum Secure Direct Communication protocol is one of the quantum communication methods that capable to transmit secure data using the quantum channel. QSDC has a very distinctive characteristic that stands out among other quantum methods. Quantum Secure Direct Communication protocol does not require the two parties communicating to share their private keys in advance.
In order to achieve its optimum security, Quantum Secure Direct Communication protocol should use the quantum memory to be effective in controlling the data transfer over a quantum network. The new finding from Professor Zhang and team has made a leap forward and answer the limitation in QSDC as discovered by Professor Forbes from Wits University. Watch the short explanation about quantum cryptography below: