Liang Zhang, Wu Jinhua, Cui Ying, Sun Hao, Ning Cun-Zheng
Department of Electronic Engineering, Tsinghua University, 100084, Beijing, China.
College of Integrated Circuits and Optoelectronic Chips, Shenzhen Technology University, 518118, Shenzhen, Guangdong, China.
Light Sci Appl. 2023 Feb 6;12(1):36. doi: 10.1038/s41377-023-01070-0.
Nanomaterials-based photoluminescence thermometry (PLT) is a new contact-free photonic approach for temperature sensing, important for applications ranging from quantum technology to biomedical imaging and diagnostics. Even though numerous new materials have been explored, great challenges and deficiencies remain that hamper many applications. In contrast to most of the existing approaches that use large ensembles of rare-earth-doped nanomaterials with large volumes and unavoidable inhomogeneity, we demonstrate the ultimate size reduction and simplicity of PLT by using only a single erbium-chloride-silicate (ECS) nanowire. Importantly, we propose and demonstrate a novel strategy that contains a self-optimization or "smart" procedure to automatically identify the best PL intensity ratio for temperature sensing. The automated procedure is used to self-optimize key sensing metrics, such as sensitivity, precision, or resolution to achieve an all-around superior PLT including several record-setting metrics including the first sensitivity exceeding 100% K (~138% K), the highest resolution of 0.01 K, and the largest range of sensible temperatures 4-500 K operating completely within 1500-1800 nm (an important biological window). The high-quality ECS nanowire enables the use of well-resolved Stark-sublevels to construct a series of PL intensity ratios for optimization in infrared, allowing the completely Boltzmann-based sensing at cryogenic temperature for the first time. Our single-nanowire PLT and the proposed optimization strategy overcome many existing challenges and could fundamentally impact PL nano-thermometry and related applications such as single-cell thermometry.
基于纳米材料的光致发光温度测量法（PLT）是一种用于温度传感的新型非接触式光子方法，对从量子技术到生物医学成像与诊断等一系列应用都很重要。尽管已经探索了众多新材料，但仍存在巨大挑战和不足，阻碍了许多应用。与大多数现有方法不同，这些方法使用大量体积大且存在不可避免不均匀性的稀土掺杂纳米材料集合，我们通过仅使用一根氯化铒 - 硅酸盐（ECS）纳米线展示了PLT的极致尺寸缩减和简易性。重要的是，我们提出并展示了一种新颖策略，该策略包含自我优化或“智能”程序，可自动识别用于温度传感的最佳PL强度比。该自动化程序用于自我优化关键传感指标，如灵敏度、精度或分辨率，以实现全面卓越的PLT，包括多项创纪录指标，其中首次灵敏度超过100% K（约138% K）、最高分辨率为0.01 K以及在1500 - 1800 nm（一个重要的生物窗口）内完全运行的4 - 500 K最大可感温度范围。高质量的ECS纳米线能够利用分辨良好的斯塔克子能级构建一系列用于红外优化的PL强度比，首次实现了在低温下完全基于玻尔兹曼的传感。我们的单纳米线PLT和所提出的优化策略克服了许多现有挑战，并可能从根本上影响PL纳米温度测量法及相关应用，如单细胞温度测量。
