Subcarrier multiplexing optical quantum key distribution (4 pages)

Hailin Xiao, Shan Ouyang, Anthony Theodore Chronopoulos

Hailin Xiao, Zhongshan Zhang

Михаил Арсеньевич Фадеев, P. A. Morozova, Semyon V. Smirnov +3 more

Arturo Ortigosa-Blanch, J. Capmany

We present the physical principles of a quantum key distribution system that opens the possibility of parallel quantum key distribution and, therefore, of a substantial improvement in the bit rate of such systems. Quantum mechanics allows for multiple measurements at different frequencies and thus we exploit this concept by extending the concept of frequency coding to the case where more than one radio-frequency subcarrier is used for independently encoding the bits onto an optical carrier. Taking advantage of subcarrier multiplexing techniques we demonstrate that the bit rate can be greatly improved as parallel key distribution is enabled.

Guhao Zhao, Zhao Shang-Hong, Zhoushi Yao +4 more

A subcarrier multiplexing quantum key distribution is based on phase modulation polarization coding scheme. The key could be shared by several parallel sideband channels, and each sideband has a random and independent polarization which is synthesized by controlling the phase difference of subcarriers in two electro-optical phase modulators. The key rate could be increased multiply. The simulation result shows that the scheme works well.

László Gyöngyösi, Sándor Imre