Vonk Sander J W, van Swieten Thomas P, Cocina Ario, Rabouw Freddy T
Debye Institute for Nanomaterials Science, Utrecht University, Princetonplein 1, 3584 CC Utrecht, The Netherlands.
Optical Materials Engineering Laboratory, ETH Zürich, Leonhardstrasse 21, 8092 Zürich, Switzerland.
Nano Lett. 2023 Jul 26;23(14):6560-6566. doi: 10.1021/acs.nanolett.3c01602. Epub 2023 Jul 14.
Ongoing developments in science and technology require temperature measurements at increasingly higher spatial resolutions. Nanocrystals with temperature-sensitive luminescence are a popular thermometer for these applications offering high precision and remote read-out. Here, we demonstrate that ratiometric luminescence thermometry experiments may suffer from systematic errors in nanostructured environments. We place lanthanide-based luminescent nanothermometers at controlled distances of up to 600 nm from a Au surface. Although this geometry supports no absorption or scattering resonances, distortion of the emission spectra of the thermometers due to the modified density of optical states results in temperature read-out errors of up to 250 K. Our simple analytical model explains the effects of thermometer emission frequencies, experimental equipment, and sample properties on the magnitude of the errors. We discuss the relevance of our findings in several experimental scenarios. Such errors do not always occur, but they are expected in measurements near reflecting interfaces or scattering objects.
科学技术的不断发展要求在越来越高的空间分辨率下进行温度测量。具有温度敏感发光特性的纳米晶体是这类应用中常用的温度计，具有高精度和远程读数功能。在此，我们证明了在纳米结构环境中，比率发光测温实验可能会受到系统误差的影响。我们将基于镧系元素的发光纳米温度计放置在距离金表面最高达600纳米的可控距离处。尽管这种几何结构不存在吸收或散射共振，但由于光学态密度的改变导致温度计发射光谱发生畸变，从而产生高达250 K的温度读数误差。我们简单的分析模型解释了温度计发射频率、实验设备和样品特性对误差大小的影响。我们讨论了我们的发现在几种实验场景中的相关性。这类误差并非总是出现，但在靠近反射界面或散射物体的测量中预计会出现。
