Low-Fidelity Entanglement Distillation with FIMAX

Abstract: Uncontrolled interactions with the environment introduce errors that remain a significant challenge to the reliability of quantum technologies using entanglement. An essential method to overcome or mitigate these errors is entanglement distillation, the transformation of multiple copies of weakly entangled states into a smaller number of approximately maximally entangled states. We present a comparative analysis of the stabilizer-based two-copy entanglement distillation protocol, FIMAX, against other recurrent two-copy protocols, including ADGJ, DEJMPS, P1-P2, and the generalized BBPSSW protocol. We focus on low-fidelity bipartite quantum states in dimensions $d = 2$ and $d = 3$, which are particularly challenging to distill. Our findings demonstrate that FIMAX exhibits superior performance for these states. While other protocols struggle with highly noisy states, FIMAX successfully distills entanglement even when the initial state quality is severely compromised. These results highlight the protocol's capability to address the effects of environmental noise, advancing the robustness and scalability of quantum technologies leveraging entanglement distillation.