Quantum network applications in 6G paradigm

Over the past four decades, quantum communication has evolved as a dynamic interdisciplinary field, advancing theoretical concepts and practical implementations. This article provides a concise overview focusing on recent progress in different aspects of secure quantum communication and quantum computation protocols, which can be applied to several real-world applications in quantum networks. These protocols guarantee unconditional security while enhancing communication rates and computation capabilities by harnessing quantum advantages. We also explore the role of non-terrestrial networks in quantum applications, with a focus on quantum technologies such as quantum key distribution and beyond, suitable for satellite-based applications. These technologies can contribute to future extensions of the quantum internet across intercontinental territories, connecting complex quantum network applications. Further, we delve into discussing the integration of quantum communication into 6G technology. The key innovation of this article lies in integrating quantum communication into 6G networks through a novel system-level simulation framework. 6G-enabled quantum networks are expected to meet the high demands on ubiquitous coverage, data rate, latency, and energy consumption. To address these issues, we design and evaluate four traffic demand scenarios using numerical simulation, illustrating how superdense coding doubles the data transmission rate and fulfills the high traffic demands on data rate, while under low traffic demand, entanglement resources can be reserved for future applications. Specifically, our investigation demonstrates how resource utilization adapts to different traffic demands, with adjustments based on available resources and practical constraints, evaluated over an ideal noise-free communication channel. The proof-of-work simulation is implemented using Python and is based on the system model we designed for varying traffic demands to pave the way for efficient quantum networks and gain deeper insights into their feasibility with available resources.