Photothermal lens spectroscopy at ICTP: Evolution, progress, and applications beyond the Gallieno Denardo era

H Cabrera
The Abdus Salam International Centre for Theoretical Physics, Strada Costiera 11, 34151 Trieste, Italy

In memory of Professor Gallieno Denardo, ICTP Italy

The thermal lens technique relies on measuring the temperature increase in a sample caused by nonradiative relaxation of the energy absorbed from a light source. This technique is indeed highly sensitive due to the direct absorption of light and its immediate conversion into heat. Because of its high sensitivity, the thermal lens technique is widely used in fields like material science, nanotechnology, chemistry, and biosensing. It can be used to analyze the optical properties of materials, measure energy absorption, and even detection of impurities in samples. It is also useful for studying the dynamics of photochemical reactions, as it provides detailed information about how energy is absorbed and dissipated in the material. This article reviews the development of thermal lens spectrometry at ICTP in the many years following Gallieno Denardo’s passing, focusing on recent advances. This overview begins with an explanation of the technique’s underlying theory, followed by a discussion of its instrumentation and applications, highlighting the unique characteristics of the technique. It covers applications for environmental research, material characterization, and biomedical fields. The article concludes with proposals of TLS’s for future development, focusing on its potential applications in emerging research fields. © Anita Publications. All rights reserved.
Doi: xxx
Keywords: Thermal lens spectrometry, Photothermal effects, Collimated probe beam.

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