The seven-year QuNET initiative funded by the Federal Ministry of Education and Research is subdivided into three phases: In the first phase QuNET-alpha, the project partners develop quantum communication technologies for hybrid communication systems, and set up a secured pilot route between federal agencies. The principal goal is to develop a quantum network that ensures that data transmission between federal agencies is secure against manipulation and eavesdropping. For this purpose, in QuNET-alpha the Fraunhofer Heinrich Hertz Institute develops photonic technologies for secure quantum-based communication networks together with the Fraunhofer IOF, the Max Planck Society MPG, and the German Aerospace Center DLR.
The Fraunhofer HHI is contributing two pioneering technologies to QuNET: photonic integrated circuits for the quantum network as well as expertise in fiber optic networks and in quantum key distribution. As a result, the Fraunhofer HHI covers the entire chain of key functionalities from integrated optical components to real-time systems for fiber-based quantum communication. In QuNET-alpha, the component development focuses on transmitters for the BB84 quantum cryptography protocol based on the HHI-PolyBoard platform, as well as on InP-based single photon detectors for future miniaturized receiver chips. On the system side, the focus is on real-time quantum cryptography setups for the provision of secure keys via existing fiber optic networks. In addition, the Fraunhofer HHI provides the classic mobile radio and fiber optics communication channels for all project partners, which are encrypted using quantum cryptography and, thus, enable confidential communication.