Quantum Key Distribution Post-processing: A Heterogeneous Computing Perspective

Recent experimental demonstrations of quantum key distribution (QKD) have caught worldwide attention for their ability to transmit encryption keys. Current commercial QKD typically uses discrete optical components, resulting in systems which are typically sized to fit within telecommunications racks. Widespread deployment of QKD systems will require low-SWaP (i.e., Size, Weight, and Power) QKD systems, thus Photonic Integration is seen as a key enabler of widespread adoption. QKD post-processing systems play a significant role in the distillation and high-speed generation of secure keys for discrete variable (DV) or continuous variable (CV) QKD protocols. Interest in using heterogeneous computing techniques for QKD post-processing is growing, owing to the emergence of domain-specific hardware accelerators for efficient quantum information processing applications. We hence discuss in a tutorial manner the principles and techniques of QKD post-processing. Characteristics of representative heterogeneous platforms for QKD post-processing implementations are compared, along with a review of the state-of-the-art QKD post-processing accelerators.