Chip-based devices improve practicality of quantum-secured communication

New chip-based devices contain all the optical components necessary for quantum key distribution. The cost-effective platform is designed to facilitate citywide networks. Credit: Henry Semenenko, University of Bristol

Researchers at University of Bristol, UK, have demonstrated new chip-based devices that contain all the optical components necessary for quantum key distribution while increasing real-world security.

This fast and cost-effective platform is poised to facilitate implementation of extremely secure data communication that can be used to protect everything from emails to online banking information.

The researchers report that secure quantum key exchange can be accomplished between two chip-based devices — measuring just 6 x 2 millimeters — potentially over a fiber network with links up to 200 kilometers long. Using two independent chip devices, they showed that error rates and speed were comparable to state-of-the-art, commercial components.

The new quantum key distribution devices are based on the same semiconductor technology found in every smartphone and computer. Instead of wires to guide electricity, they contain highly complex circuits that control the weak photonic signals of light necessary for quantum key distribution. Nanoscale components in the chips make it possible to drastically reduce the size and power consumption of quantum communication systems while maintaining high-speed performance vital for modern networks.

The paper has been published in Optica, The Optical Society‘s (OSA) journal. (

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