Spectrochim Acta A Mol Biomol Spectrosc
February 2025
The growing interest in using photodynamic therapy for cancer treatment and antimicrobial applications has prompted the search for different classes of dyes. In general, the protocols of these studies are different, making it difficult to compare their efficiency directly. Here, we apply a controlled protocol to analyze the photophysical properties of Erythrosin B, Eosin Y, and Rose Bengal using a set of optical techniques.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
September 2024
Rhodamines constitute a class of dyes extensively investigated and applied in various contexts, primarily attributed to their high luminescence quantum yield. This study delves into the impact of aggregation on the thermal and optical properties of Rhodamine 6G (R-6G) solutions in distilled water. Examined properties encompass thermal diffusivity (D), temperature coefficient of the refractive index (dn/dT), fluorescence quantum efficiency (η), and energy transfer (ET).
View Article and Find Full Text PDFThe interaction of localized light with matter generates optical electrostriction within dielectric fluids, leading to a discernible change in the refractive index of the medium according to the excitation's light profile. This optical force holds critical significance in optical manipulation and plays a fundamental role in numerous photonic applications. In this study, we demonstrate the applicability of the pump-probe, photo-induced lensing (PIL) method to investigate optical electrostriction in various dielectric liquids.
View Article and Find Full Text PDFPiezo-optic and thermo-optic coefficients are important material properties that play a critical role in the design and optimization of many optical devices. The ability to accurately measure and control these coefficients is essential for achieving high performance and reliability in a wide range of applications. In this article, we use the optical detection of the ultrasound-induced thermal lens effect to investigate these properties for water at low temperatures.
View Article and Find Full Text PDFWe present semi-analytical solutions describing the spatiotemporal distributions of temperature and pressure inside low-absorbing dielectrics excited by tightly focused laser beams. These solutions are compared to measurements in water associated with variations of the local refractive index due to acoustic waves generated by electrostriction, heat deposition, and the Kerr effect at different temperatures. The experimental results exhibited an excellent agreement with the modeling predictions, with electrostriction being the dominant transient effect in the acoustic wave generation.
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