Quantum networks at INQNET

Quantum networks promise accelerated development across various fields, including secure communication, computing, quantum simulations, metrology, and sensing. Despite being in their early stages, the development phases and corresponding applications of quantum networks are well-identified, paving the way for a large-scale quantum internet. Here, we report our progress in these stages, focusing on the distribution of weak coherent states, the generation and distribution of entangled states in both traditional two dimensions and higher dimensions. We highlight key milestones achieved, such as high clock rate time-bin quantum key distribution, high rate time-bin entanglement generation and distribution using ultra-low loss fiber, high-dimensional entanglement generation in the temporal degree of freedom, entanglement swapping over real-world fiber links, its coexistence with classical communication, and the development of integrated photonics for beam steering in free-space quantum communication.