论文标题
检测单个红外光子达到最佳系统检测效率
Detecting single infrared photons toward optimal system detection efficiency
论文作者
论文摘要
具有近乎一体系统效率的超导纳米线单光子检测器（SNSPD）是一个关键的支持，但对于众多量子基本理论验证和量子信息应用，仍然难以捉摸的技术。关键的挑战是，对于具有有限的填充比的曲折纳米线同时具有几乎不合同的光子响应概率和吸收效率，这对NBN比其他过渡温度较低的其他超导材料（例如WSI）更为重要。在这里，我们通过在介电镜上用双层纳米线代替单层纳米线来克服上述挑战，并以创纪录的系统效率产生NBN SNSPD。在0.8 K处的检测器显示，最大系统检测效率（SDE）为1590 nm的98％，在1530-1630 nm的波长范围内，系统效率超过95％。此外，使用紧凑的两级冷冻机器人在1550 nm处的检测器在1550 nm处显示出最大的SDE。这种类型的检测器还显示了针对各种参数的鲁棒性，例如纳米线的几何大小和光谱带宽，可在2.1K时在2.1K时在同一运行中制造的45个检测器的SDE高收率为73％（36％），而SDE的SDE在2.1K时为2.1K（90％）。这些由双层纳米线制成的SNSPD对于批处理生产具有重要的实际意义。
Superconducting nanowire single-photon detector (SNSPD) with near-unity system efficiency is a key enabling, but still elusive technology for numerous quantum fundamental theory verifications and quantum information applications. The key challenge is to have both a near-unity photon-response probability and absorption efficiency simultaneously for the meandered nanowire with a finite filling ratio, which is more crucial for NbN than other superconducting materials (e.g., WSi) with lower transition temperatures. Here, we overcome the above challenge and produce NbN SNSPDs with a record system efficiency by replacing a single-layer nanowire with twin-layer nanowires on a dielectric mirror. The detector at 0.8 K shows a maximal system detection efficiency (SDE) of 98% at 1590 nm and a system efficiency of over 95% in the wavelength range of 1530-1630 nm. Moreover, the detector at 2.1K demonstrates a maximal SDE of 95% at 1550 nm using a compacted two-stage cryocooler. This type of detector also shows the robustness against various parameters, such as the geometrical size of the nanowire, and the spectral bandwidth, enabling a high yield of 73% (36%) with an SDE of >80% (90%) at 2.1K for 45 detectors fabricated in the same run. These SNSPDs made of twin-layer nanowires are of important practical significance for batch production.
