High dimensional entanglement

Quantum entanglement serves as a key resource in quantum information processing, including quantum communication. During the distribution of entanglement through fiber or free space, photons—commonly employed as carriers—suffer from losses and are affected by atmospheric turbulence, which degrades the quality of the entanglement. Recent advancements have demonstrated that higher-dimensional entanglement offers greater resilience to loss and noise compared to qubits. In this work, we investigate pulsed and continuous high-dimensional time-bin sources in detail. Using these sources, we certify high-dimensional entanglement up to dimension 32. Beyond certification, we demonstrate that a secure key rate can be distilled in the asymptotic limit up to dimension 32. Future work will focus on evaluating the robustness of high-dimensional entanglement against noise and loss. We also discuss the potential of these sources for future free-space and fiber-based quantum communication systems.