Entanglement is known to significantly improve the performance (separately) of communication and detection schemes that utilize quantum resources. This work explores the simultaneous utility of quantum entanglement for (joint) communication and detection schemes, over channels that are convex combinations of identity, depolarization and erasure operators, both with perfect and imperfect entanglement assistance. The channel state is binary, rapidly time-varying and unknown to the transmitter. While the communication is delay-tolerant, allowing the use of arbitrarily long codewords to ensure reliable decoding, the channel state detection is required to be instantaneous. The detector is neither co-located with the transmitter, nor able to wait for the decoding in order to learn the transmitted waveform. The results of this work appear in the form of communication-rate vs instantaneous-detection-error tradeoffs, with and without quantum entanglement. Despite the challenges that place the two tasks at odds with each other, the results indicate that quantum entanglement can indeed be simultaneously and significantly beneficial for joint communication and instantaneous detection.

翻译：已知量子纠缠能显著提升利用量子资源的通信与检测方案（分别）的性能。本研究探讨了量子纠缠在（联合）通信与检测方案中的同步效用，所涉信道为恒等算子、去极化算子与擦除算子的凸组合，并涵盖完美与非完美纠缠辅助情形。信道状态为二进制、快速时变且对发送端未知。通信具有延迟容忍性，允许使用任意长码字确保可靠解码，而信道状态检测则需瞬时完成。检测器既未与发送端共置，亦无法等待解码过程以获知发送波形。本研究结果以通信速率与瞬时检测误差的权衡关系呈现，涵盖有/无量子纠缠两种情形。尽管两类任务因各自挑战而存在矛盾，结果表明量子纠缠确实能对联合通信与瞬时检测产生同步且显著的增益。