AWS says it has made a breakthrough in quantum networking that could also boost the speed and efficiency of classical telecom networks. Working with Harvard University, researchers at Amazon’s cloud platform created a new packaging method for optical fibres that solves a long-standing problem with data degradation at a distance.
Quantum communication is a rapidly advancing field as the world moves from classical to post-quantum cryptography standards and from metal to light-based networking cables. The problem is that fibre optic cable systems struggle with data degradation over long distances, particularly when working with quantum data or in extreme temperature environments. These include issues connecting a fibre and a device on a larger scale, developing light modulators for high-speed classical communication, or co-packaged optics for data centres.
There have been experiments with new types of cable and entanglement systems recently, including one between the UK and Ireland to try and solve this problem. In some cases it involves the addition of new equipment to encode the data, other solutions involve network packaging.
Why packaging is key to quantum communication
In optical networking, packaging is a key component and an active area of research. It is the process of housing or enclosing optical components such as lasers, detectors, or fibres in a manner that protects them, ensures their correct alignment, and facilitates their interaction or connection with other components. It is felt improved packaging holds the key to solving the distance problem for quantum networking.
Light in optical fibres is confined to a region with a diameter of a fraction of the size of a single human hair. This creates a fragile environment with extremely precise alignment of components, which can easily be disrupted. This becomes especially challenging for low-temperature operations used by many quantum devices. For AWS, improving the packaging is an important step towards the goal of creating a system that works in all environments, including where cables may be laid across a road.
Central to this is packing the fibre optic cable with quantum repeaters that can re-encode data, correct photon loss in real-time and do so without disrupting the quantum nature of the information being carried down the fibre optic cable.
In the new AWS method, a tapered end of the optical fibre is put in physical contact with a tapered end of the optical device, such as the quantum repeater, allowing light to gradually pass through the interface. Forces between tapered ends give the interface immunity against small displacements of the components, such as if it is buried under a road and the noise of the traffic causes minor disruptions in the placement of the cable.
As well as working at cryogenic temperatures, AWS scientists say that this can also be packaged with the types of modulators used in high-speed telecommunication networks. As quantum computers and quantum networking become more common, it could also allow cheaper and more efficient interfaces between quantum and classical hardware.
Read more: First quantum communications link tested between UK and Ireland
