Routing in Quantum Repeater Networks with Mixed Noise Figures

Quantum network holds the key to the next generation of secure communication, long-distance communication, and quantum internet. Due to inherent quantum effects, routing in the quantum network is a major challenge. This study explores a realistic approach to routing in quantum networks which aims to mirror real-world networks by segregating sources and destinations from the network. By addressing practical constraints we examine the impact of heterogeneous nodes on network performance. In particular, we focused on performance in terms of the ratio of high-quality to total nodes and path establishment order. This work unveils relationships between them and communication path fidelity. It highlights the critical role of the fraction of high-quality nodes in end-to-end fidelity and explores the trade-offs between upgrading all nodes to high quality or retaining a subset of lower-quality nodes. Our simulations show that incorporating the knowledge of node quality not only helps in strategically boosting the fidelities of some of the routing paths but also reduces the number of blocked paths in the quantum network.