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arXiv · 2206.07030

Synchrotron-based near-field photothermal microspectroscopy: Development of a quantitative nanohistology set-up with expansion of the infrared capability 2

Abstract

The purpose was two-fold: To explore the capability of the Diamond Synchrotron infra-red so as to include near-field photothermal microspectroscopy (PTMS); and Toward a quantitative nanohistology - investigation of scleroderma using synchrotron radiation (mu- FTIR). With recent advances in AFM, the integration of an IR temperature-based system on an IR beamline is still a promising and unique approach. These preliminary tests of the PTMS stand-alone system with the Diamond Multimode InfraRed Imaging and Microspectroscopy beamline (MIRIAM) were successful in one beamtime. To our knowledge, this is still among very few studies worldwide that managed to interface an AFM-resistive probe to measure an infrared spectrum using synchrotron radiation (SR) as a source. When the alignment was successful, we managed to obtain good spectra on samples that were strong infrared absorbers. However, the alignment could not be guaranteed all the time, and the signal-to-noise ratio became too low to record any meaningful spectra on samples deemed of scientific interest for this proposal. We clarified the possible improvements to PTMS instrumentation and data acquisition needed to ensure that we can collect sufficient thermal signals from very thin samples.

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L Bozec, G Cinque, M Reading, H M Pollock. 2022-05-30. Synchrotron-based near-field photothermal microspectroscopy: Development of a quantitative nanohistology set-up with expansion of the infrared capability 2. https://arxiv.org/abs/2206.07030

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