Merging-based quantum repeater

Abstract

We introduce a merging-based quantum repeater that departs from the conventional swapping paradigm by progressively growing multipartite entanglement. In contrast to swapping-based schemes, where a single failed operation often forces the entire protocol to restart, our approach reuses previously established entanglement through iterative gap-patching, thereby reducing waiting times, improving distribution rates, and introducing enhanced flexibility in the communication requests. We analyze this protocol in the context of probabilistic operations and a time-dependent dephasing noise model. We compare it with standard repeater protocols and demonstrate a clear advantage in secret-key rate across relevant operating regimes, underscoring its potential for practical quantum communication scenarios. These results establish merging-based repeaters as a promising alternative design principle for scalable and resource-efficient quantum-network architectures.