POLARISATION QUANTUM CRYPTOSYSTEM Russian patent published in 2009 - IPC H04L9/14 

FIELD: information technology.

SUBSTANCE: present invention relates to quantum cryptosystems and can be used for generating secret keys, used for encoding information in quantum data transfer systems. The polarisation quantum cryptosystem has transmitting and receiving sides. The transmitting side comprises a first unit for generating a secret key, the output of which is the first output of the cryptosystem, first and second random number generators, single photon laser and a polarisation modulator. The receiving side comprises a second unit for generating a secret key, the output of which is the second output of the cryptosystem, a third random number generator, polarisation beam splitter, fixed mirror, and first and second photon detectors. The data exchange input/output of the second unit for generating secret key is connected to the first non-classified communication channel. The polarisation quantum cryptosystem also contains a polarisation modulator, first quantum communication channel, second non-classified communication channel, device for measuring the complete set of Bell states, second quantum communication channel, source of polarisation-mixed up photon pairs and a third quantum communication channel.

EFFECT: increased propagation distance of secret key.

1 dwg, 1 tbl