System and method for measuring device-independent quantum key distribution (QKD)

Abstract

The invention provides a system and method for measuring device-independent quantum key distribution (QKD). The system comprises a first-party device, a second-party device and a third-party device which are connected through a transmission channel, wherein both the first-party device and the second-party device comprise a controller, a processor and multiple lasers; the multiple lasers are used for respectively preparing the signal states and decoy states corresponding to two eigenstates of the signal measurement base and decoying the two decoy states of the measurement base; the controller selects one of the two groups of measurement bases, selects the signal states or the decoy states prepared by the corresponding lasers according to the selected measurement bases, and sends the signal states or the decoy states to the third-party device; the processor implements key post-processing on the received measurement results to obtain a secure key; and the third-party device implements Bell-state measurement on the received quantum state and releases the measurement results. By adopting the system and method provided by the invention, the number of the adopted lasers can be reduced without decreasing the performance of a QKD system, and thus the cost of the device can be lowered, the complexity of the device can be reduced, and more space of the client device can be saved.

Description

technical field

[0001] The invention relates to the technical field of quantum information, in particular to a measurement-equipment-independent quantum key distribution system and method. Background technique

[0002] Quantum key distribution (QKD) technology is a technology based on quantum mechanics. This technique provides a way for two legitimate users: Alice and Bob to share keys securely even in the presence of Eve, the eavesdropper. After successfully sharing the key, the two users can use the shared key to encrypt the information they want to transmit, so as to realize secure communication.

[0003] In the quantum key distribution technology, the BB84 protocol is the most famous and widely used quantum key distribution protocol. In this protocol, the photons are encoded by the polarization of light, and the photons are randomly encoded in the horizontal and vertical polarization bases (that is, the Z base, also known as the direct measurement base) or the positive...

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