Simultaneous Distribution of Two Quantum Keys When Transmitting Single Photons with Wavelengths of 780 and 850 nm via a Single Free-Space Quantum Channel
摘要
The article presents the experimental implementation of a method for increasing the quantum key distribution rate in free-space quantum-cryptographic communication lines by simultaneously transmitting single photons with wavelengths of 780 and 850 nm via a single quantum channel. The laboratory system we created demonstrated an approximately twofold increase in the distribution rate of the so-called ‘‘sifted’’ quantum key by using two setups operating at wavelengths of 780 and 850 nm and transmitting photons via one quantum channel 23 cm long. The distribution rate of the sifted quantum key and the quantum bit error rate for a wavelength of 780 nm was