Tip-enhanced Raman spectroscopy (TERS) is currently widely recognized as an essential but still emergent technique for exploring the nanoscale. However, our lack of comprehension of crucial parameters still limits its potential as a user-friendly analytical tool. The tip’s surface plasmon resonance, heating due to near-field temperature rise, and spatial resolution are undoubtedly three challenging experimental parameters to unravel. However, they are also the most fundamentally relevant parameters to explore, because they ultimately influence the state of the investigated molecule and consequently the probed signal. Here we propose a straightforward and purely experimental method to access quantitative information of the plasmon resonance and near-field temperature experienced exclusively by the molecules directly contributing to the TERS signal. The detailed near-field optical response, both at the molecular level and as a function of time, is evaluated using standard TERS experimental equipment by simultaneously probing the Stokes and anti-Stokes spectral intensities. Self-assembled 16-mercaptohexadodecanoic acid monolayers covalently bond to an ultra-flat gold surface were used as a demonstrator. Observation of blinking lines in the spectra also provides crucial information on the lateral resolution and indication of atomic-scale thermally induced morphological changes of the tip during the experiment. This study provides access to unprecedented molecular-level information on physical parameters that crucially affect experiments under TERS conditions. The study thereby improves the usability of TERS in day-to-day operation. The obtained information is of central importance for any experimental plasmonic investigation and for the application of TERS in the field of nanoscale thermometry.

目前，尖端增强拉曼光谱（TERS）被广泛认为是探索纳米级的必不可少的技术，但仍是新兴技术。但是，由于我们缺乏对关键参数的理解，仍然限制了其作为用户友好的分析工具的潜力。尖端的表面等离子体激元共振，由于近场温度升高引起的加热以及空间分辨率无疑是三个有挑战性的实验参数。但是，它们还是最基本相关的参数，因为它们最终会影响所研究分子的状态，进而影响所探测的信号。在这里，我们提出了一种简单而纯粹的实验方法，以访问直接由TERS信号贡献的分子所经历的等离振子共振和近场温度的定量信息。使用标准的TERS实验设备，通过同时探测斯托克斯和反斯托克斯光谱强度，评估分子水平和时间的详细近场光学响应。共价结合到超平坦金表面的自组装的16-巯基六十二烷酸单层用作演示剂。观察光谱中的闪烁线还可以提供有关横向分辨率的重要信息，以及在实验过程中原子级热诱导尖端形态变化的指示。这项研究提供了有关物理参数的空前分子水平的信息，这些信息会严重影响TERS条件下的实验。因此，该研究提高了TERS在日常操作中的可用性。