Low-loss high-speed polarization controller with low driving-voltage and light quantum polarization state control module

Abstract

The invention discloses a low-loss high-speed polarization controller with low driving-voltage and a light quantum polarization state control module. While a lithium-niobate electro-optic polarizationcontroller in the prior art keeps high-response rate, driving voltage and part insertion loss of the lithium-niobate electro-optic polarization controller are reduced. Device dimension is reduced. Stability of working performance of a device is enhanced. In order to further reduce loss and size of the light quantum polarization state control module at the receiving end of a quantum key distribution system, the invention brings forward the light quantum polarization state control module integrated with the lithium-niobate electro-optic polarization controller and a polarization beam splitter.Therefore, great support is provided for low construction cost, high communication speed, and long transmission distance of quantum secret communication technology.

Description

technical field [0001] The invention relates to quantum secret communication fields such as quantum key distribution and generation of quantum entangled photon pairs, in particular to a high-speed polarization controller with low loss and low driving voltage and an optical quantum polarization state control module. Background technique [0002] In recent years, the quantum secret communication technology based on the quantum key distribution system adopts the method of transmitting quantum keys to provide an "absolutely safe" communication method that cannot be eavesdropped in theory. The "absolute security" of quantum secure communication technology comes from the unique quantum physical characteristics such as the unclonability and uncertainty of the information carrier - light quantum. [0003] At the receiving end of the quantum key distribution system, it is necessary to ensure that the spectral information, timing information, polarization information and other multi-d...

AI Technical Summary

Problems solved by technology

[0006] Compared with fiber extrusion type polarization controllers, the disadvantages of lithium niobate electro-optic polarization controllers are mainly longer device length and larger device insertion loss

[0007] First of all, the longer device length not only increases the volume of the polarization control device at the receiving end of the quantum key distribution system, but also is not conducive to the modular integration of lithium niobate electro-optical polarization controllers with other devices (such as polarization beam splitters) or even a single On-chip integration (otherwise the device size is larger)

[0008] Secondly, the larger insertion loss of the device reduces the number of photons reaching the single-photon detector, so that the receiving end of the quantum key distribution system has to use a single-photon detector with higher detection sensitivity and lower dark count, and at the same time reduce the number of The distance between the communication nodes of the quantum key distribution network undoubtedly increases the technical difficulty and construction cost of the quantum key distribution system

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