Quantum key distribution phase encoder/decoder, corresponding encoding/decoding device and system

Abstract

The invention provides a quantum key distribution phase encoder / decoder and a corresponding encoding / decoding device and system. The phase encoder / decoder comprises: a beam splitter; two polarizationorthogonal rotation reflection devices optically coupled with the beam splitter through two arms respectively; one or each of the two reflection devices includes a polarization beam splitter having aninput port and two output ports, the input port is coupled to a corresponding arm; two output ports of each polarization beam splitter are coupled through a transmission light path, at least one reflection device comprising the polarization beam splitters is provided with a phase modulator and a half-wave plate on the transmission light path, and the included angle between the polarization direction of light pulses input into the half-wave plate and the fast axis or the slow axis of the half-wave plate is 45 degrees. According to the invention, encoding and decoding interference can be stablycarried out on input light pulses in any polarization state, the problem that a system cannot stably work due to polarization induced fading in phase encoding and time bit-phase encoding quantum keydistribution application is solved, and meanwhile, the loss at an interferometer is reduced.

Description

technical field [0001] The invention relates to the technical field of optical transmission secure communication, in particular to a quantum key distribution phase codec based on polarization orthogonal rotation reflection, a corresponding codec device including the phase codec, and a quantum key distribution system. Background technique [0002] Quantum secure communication technology is a frontier hot field combining quantum physics and information science. Based on the quantum key distribution technology and the principle of one-time pad cryptography, quantum secure communication can realize the secure transmission of information in open channels. Quantum key distribution is based on physical principles such as the Heisenberg uncertainty relation in quantum mechanics and the quantum non-cloning theorem. It can safely share keys among users and detect potential eavesdropping behaviors. It can be applied to national defense, government affairs, Fields with high security in...

AI Technical Summary

Problems solved by technology

[0006] The main purpose of the present invention is to propose a quantum key distribution phase codec based on polarization orthogonal rotation reflection, a corresponding codec device including the phase codec and a quantum key distribution system to solve phase coding and time bit - Dilemma of phase decoding interferometric instabilities caused by polarization-induced fading in phase-encoded quantum key distribution applications while reducing losses at the interferometer

Images