标题： 多光子在超紧凑逆向设计的多端口光束分裂器中的量子干涉 显示英文标题

标题： Multiphoton Quantum Interference at Ultracompact Inverse-Designed Multiport Beam Splitter

摘要： 当光子集成电路实现时，光量子技术进入了一个新阶段，这在实际应用中取得了巨大进展。 为了追求高集成密度和低电路复杂度，拓扑优化提供的超紧凑设备为进一步小型化这些光子系统提供了一种有前景的解决方案。 然而，尽管不断开发，它们在量子实验中的潜力尚未得到充分探索。 在这项工作中，我们使用尺寸为 8.0 $\rm{\mu}$m $\times$ 4.5 $\rm{\mu}$m 的拓扑优化三路分束器演示了多光子量子干涉。我们通过单光子和双光子统计特性表征了该三路分束器并重建了其传递矩阵。 我们还利用该三路分束器进行了 heralded 三光子量子干涉。 测量到的四重符合计数具有 (-47.9$\pm$ 8.6)% 的可见度峰值，这与从重建的传递矩阵预测的 -55.8% 相符。 我们的工作证实了在超紧凑干涉仪中成功实现了多光子量子干涉，并展示了利用拓扑优化的多端口干涉仪在量子技术各个领域的可能性。 显示英文摘要

摘要： Photonic quantum technologies enter a new phase when realized in photonic integrated circuits, leading to a great advance in practical applications. In the pursuit of high integration density and low circuit complexity, ultracompact devices delivered by topology optimization offer a promising solution to miniaturize these photonic systems even further. However, their potential for quantum experiments has not yet been fully explored despite the constant development. In this work, we demonstrate multiphoton quantum interference using a topology-optimized tritter with a size of 8.0 $\rm{\mu}$m $\times$ 4.5 $\rm{\mu}$m. We characterize the tritter and reconstruct its transfer matrix by means of single- and two-photon statistics. We also perform heralded three-photon quantum interference with the tritter. The measured four-fold coincidence features a peak with visibility of (-47.9$\pm$ 8.6)%, which is in fair agreement with the prediction of -55.8% estimated from the reconstructed transfer matrix. Our work confirms successful multiphoton quantum interference at an ultracompact interferometer and demonstrates the possibility of utilizing topology-optimized multiport interferometers in various fields of quantum technologies.