中国科学家研发出100通道单光子探测器，这一突破有望为宽带量子网络铺平道路。
Chinese scientists have developed a 100-channel single-photon detector, a breakthrough promising to pave the way for broadband quantum networks.
作为支撑光子量子技术的核心组件，最先进的单光子探测器此前最多只能支持32个光子信号探测通道。
State-of-the-art single-photon detectors – essential components underpinning photonic quantum technologies – could previously support a maximum of 32 detection channels for photon signals.
如今，上海一个研究团队新研发的互联方案打破了这一瓶颈，在保持精准稳定运行的同时，支持超过100个探测通道。
Now, a newly developed interconnect scheme by a Shanghai-based team has broken this bottleneck, supporting more than 100 detection channels while maintaining accurate and stable operation.
作者在论文中表示：“这项工作为大规模量子光子应用建立了稳健且可扩展的基础设施。”
“This work establishes a robust and scalable infrastructure, paving the way for large-scale quantum photonic applications,” the authors said in their paper.
这一突破由中国科学院上海微系统与信息技术研究所（上海微系统所）研究人员实现，相关成果于9月下旬发表在同行评审期刊《激光与光子学评论》上。
Achieved by researchers at the Shanghai Institute of Microsystem and Information Technology (SIMIT) under the Chinese Academy of Sciences, the breakthrough was published in the peer-reviewed journal Laser & Photonics Reviews in late September.
光子量子技术的进步正加速其从实验室演示向量子计算、通信和计量等领域的实际应用过渡。这些系统的规模化迫切需要大规模、并行的单光子探测能力。
Advances in photonic quantum technologies are accelerating their transition from laboratory demonstrations to practical applications in fields such as quantum computing, communications and metrology. The scaling of these systems urgently requires large-scale, parallel single-photon detection capabilities.
论文指出，超导纳米线单光子探测器（SNSPD）——利用超导材料的极高灵敏度探测单个光子的高端光电器件——代表了目前最先进的技术，其探测效率接近100%。
Superconducting nanowire single-photon detectors (SNSPDs) – high-end optoelectronic devices that use the extreme sensitivity of superconducting materials to detect individual photons – represent the most advanced technology available, boasting a detection efficiency approaching 100 per cent, the paper said.
凭借高探测效率、快速响应速度和高时间分辨率等优势，它们被广泛用作光子量子技术、光探测和测距（激光雷达）以及单光子成像的核心组件。然而，这些系统的规模化扩展长期以来一直是一个技术难题。
Owing to advantages including high detection efficiency, fast response speeds and high time resolution, they are widely used as core components in photonic quantum technologies, light detection and ranging (lidar), and single-photon imaging. However, scaling these systems up has long been a technical headache.
温度是一大挑战。这类探测器需要将超薄的超导纳米线薄膜冷却到接近绝对零度的低温环境，然后用电缆将其连接到室温环境，以便将探测到的信号向外传输。
Temperature poses a major challenge. Such detectors rely on cooling an ultra-thin superconducting nanowire film to a cryogenic environment approaching absolute zero. A cable is then used to connect it to a room-temperature environment to transmit the detected signals externally.
传统上使用的是同轴电缆，相对较粗，且其金属材料导热性很强。来自室温端的热量会持续沿着电缆向下传导进入低温腔体，这种现象被称为热负载。
Coaxial cables are traditionally used and relatively thick, and their metal materials are highly thermally conductive. Heat from the room-temperature end continuously conducts down the cables into the cryogenic chamber, a phenomenon known as thermal load.
当探测通道——即用于接收、处理和输出光子信号的独立专用信息通路——数量扩展到数十甚至数百条时，庞大的线缆束会给低温环境带来沉重的热负载。
When the number of detection channels – independent, dedicated informational routes for receiving, processing and outputting photon signals – expands to dozens or hundreds, the massive bundle of cables introduces a heavy thermal load to the cryogenic environment.
这大幅增加了系统的体积和制冷功耗。此前，标准装置只能支持约32个通道。
This dramatically increases the system’s size and cooling power consumption. Previously, standard set-ups could only support about 32 channels.
为克服这一难题，上海团队进行了全面重新设计。他们开发出一种名为“高密度多芯微带线”的超薄专用柔性材料。
To overcome this, the Shanghai team undertook a comprehensive redesign. They developed ultra-thin, specialised flexible materials known as “high-density multi-core microstrip lines”.
新材料和新结构具有很高的隔热性能。据团队介绍，泄漏进系统的热量仅为传统粗电缆所产生热量的二十一分之一。
The new material and structure are highly thermally insulating. According to the team, the heat leaked into the system is just one twenty-first of that generated by traditional thick cables.
研究人员还通过一系列架构创新，实现了这种大规模并行设计的稳定性和小型化。
The researchers also achieved stability and miniaturisation for this large-scale parallel design through a series of architectural innovations.
在典型制冷功率下，该系统可轻松支持100多个独立探测通道，同时保持长期稳定性。
Under typical cooling power, the system comfortably supports more than 100 independent detection channels while maintaining long-term stability.
在连续七天24小时的测试中，低温平台的温度稳定保持在2.1K以下——这一极低温度非常接近“绝对零度”的物理极限（0K，即零下273.15摄氏度）。
During a continuous seven-day 24-hour test, the cryogenic platform’s temperature remained steadily below 2.1K – an extreme low temperature extraordinarily close to the physical limit of “absolute zero” (0K, or -273.15 degrees Celsius).
测试结果还显示，所有通道均实现了超过80%的系统探测效率，同时信号误报率极低。
Test results also showed that all channels achieved a system detection efficiency exceeding 80 per cent, coupled with incredibly low signal false alarm rates.
为证明该平台在真实场景中的能力，团队搭建了一个五用户全连接的量子纠缠分发网络。
To prove the platform’s capabilities in real-world scenarios, the team built a five-user, fully connected quantum entanglement distribution network.
该装置在五名用户之间形成了10条双向量子链路，每名用户通过新开发的通道接收纠缠光子。
The set-up formed 10 two-way quantum links among the five users, with each user receiving entangled photons via the newly developed channels.
测试结果显示，全部10条链路的通信保真度——即量子信道保持信息完好的程度——均超过90%。
Test results revealed that the communication fidelity – how well a quantum channel preserves information – exceeded 90 per cent across all 10 links.