Technology highlights include:
• The world’s first three-node network connecting quantum processors. This network showcased the ability to produce entanglement between two diamond processors not directly connected by an optical fiber via an intermediary third node (also a diamond processor) without post-selection. In doing so, QIA also developed a phase-stabilized architecture that allows for more nodes to be added. Quantum processors connected to a quantum network can be used as sophisticated end nodes, paving the way for users to run advanced quantum network applications in the future.
• The world’s first quantum software and network stack. This stack was integrated with, and tested on the above multi-node network, and allows applications to be programmed in platform-independent software and run on the first quantum network operating system (QNodeOS), which was made by QIA. This makes QIA’s processing nodes programmable in high-level platform-independent software without the need to understand the physics of the underlying devices. QIA’s stack also includes the first link layer protocol, which turns entanglement generation into a reliable and platform-independent service, akin to the function of classical link layer protocols such as Ethernet or WiFi.
• An elementary link of a quantum repeater extendable to long distances that is state-of-the-art world-wide. This link enables heralded entanglement generation between two rare-earth ion quantum memories at telecom wavelengths at record rates, and opens the door to linking diverse quantum devices in metropolitan networks via long-distance repeater backbones in future developments. Such backbones would pave the way for making advanced quantum network applications available to distant users, and enabling end-to-end secure communication over long distances.
• A Blueprint for how to scale QIA’s technology to the next step. QIA has built an extensive simulation platform using its discrete event simulator for quantum networks (NetSquid), including models for QIA devices and parameter optimization on the HPC system of SURF. This allows QIA to understand the requirements of building quantum networks on real-world fiber networks.
• Innovative components including, for example, a novel processed CVD diamond material (ElementSIX)an external cavity diode laser with a 1 kHz linewidth (TOPTICA), and world record high-resolution FPGA based time-to-digital converters (Swabian Instruments), that are already showing commercial value beyond the domain of quantum communication technologies.
QIA has also made many other advancements including – for example – creating entanglement between two Ion Trap processors across campus, a quantum logic gate between distant nodes based on Neutral atoms, and a record quantum memory efficiency in cold atom based quantum memories. QIA also developed the ability to connect its Ion Trap and diamond processors at telecom wavelengths. This showcases QIA’s broad capabilities, and allows several possible paths towards realizing QIA’s ambition of building large scale quantum networks in the future.