Device-independent quantum key distribution system for continuous variable measurement and its implementation method

Abstract

The invention discloses a continuous variable measurement device-independent quantum key distribution system and an implementation method thereof. The method includes the following steps that: a quantum key transmitting end first transmits a phase reference signal to a quantum key receiving end to replace the local oscillator light; the quantum key receiving end performs homodyne detection on thereceived phase reference signal; according to a measurement result, the quantum key receiving end performs phase compensation on a quantum signal; and then, the quantum key transmitting end and the quantum key receiving end send the quantum signal to a quantum key detection end, a quantum key measurement end performs homodyne detection on the received quantum signal, wherein the local oscillator light required for the homodyne detection is generated locally, and a detection result is sent to the quantum key transmitting end and the quantum key measurement end through a classical channel. According to the scheme of the invention, the security vulnerability that a local oscillator light signal is easily attacked during channel transmission can be solved, and in addition, the detection process can be placed on a third party to prevent attacks against the detector, and thus the actual security of a continuous variable quantum key distribution system can be improved.

Description

technical field [0001] The invention belongs to the technical field of optical fiber quantum communication, and relates to a device-independent quantum key distribution system based on a local local oscillator and an implementation method thereof. Background technique [0002] Quantum key distribution can ensure that the legitimate communication parties can still share keys safely when the quantum channel is eavesdropped by eavesdroppers. Its theoretical security is guaranteed by the Heisenberg uncertainty principle of quantum mechanics and the quantum non-cloning theorem. There are currently two branches of quantum key distribution, one is discrete variable quantum key distribution based on single photon detection, and the other is continuous variable quantum key distribution based on coherent detection. Compared with the discrete variable quantum key distribution protocol, in the continuous variable quantum key distribution protocol, the preparation of the quantum state is...

AI Technical Summary

Problems solved by technology

[0003] Although the theoretical unconditional security of the continuous variable quantum key has been proved, however, there is a large gap between its actual security and theoretical security. When the continuous variable quantum key distribution system is actually running, the system equipment has defects would reduce its actual security

For example, local oscillator light is a classical light with continuous variable quantum keys used to transmit phase reference, so it is easy to be attacked by a third party. The key can be obtained under the control of the local oscillator, and even the communication equipment of the two parties can be controlled by attacking the local oscillator, thereby greatly reducing the security of the continuous variable quantum key distribution.

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