Speaker
Description
This study offers a thorough and accurate photothermal analysis of natural dye thin films employing Quantitative Infrared Thermography (QIRT), aiming to assess their thermophysical properties and ascertain their compatibility for incorporation into advanced, high-performance photonic devices. Natural dyes were obtained from their botanical origins, processed to exclude non-absorbing contaminants, and applied as uniform thin layers by regulated solution-processing methods. After that, a controlled monochromatic laser source was used to irradiate the films, which caused localized thermal excitation. This made it possible to see wavelength-dependent photothermal responses that were based on the molecular absorption profiles of each dye.
A fully calibrated QIRT measuring system was used to get high-resolution, quantitative temperature fields during laser stimulation. Calibration techniques included correcting the emissivity of each dye film, subtracting background radiation, and normalizing the temporal response to get rid of instrumental drift. These processes made sure that the temperature data we got correctly showed the materials' natural photothermal properties. Using thermal-rise kinetics to look at how the temperature changed over time made it possible to find important thermophysical characteristics such the absorption-dependent heating rate, in-plane thermal diffusivity, thermal relaxation time, and steady-state photothermal conversion efficiency.
The natural dyes that were looked at were very different from each other. Some films showed a quick rise in temperature followed by effective distribution of heat to the sides, whereas others showed a delayed rise in temperature and more concentrated heat confinement. These discrepancies are due to differences in molecule structure, conjugation length, electronic transition bands, and vibrational relaxation pathways that control how absorbed light energy turns into heat. Thermal maps made with QIRT showed more information, such as the creation of localized hot patches, anisotropic heat transmission, and persistent thermal plateaus for certain types of dye. These kinds of thermal behaviors are very important for the design and performance of photonic devices that depend on regulated optical-to-thermal coupling. These include optical limiters, thermal modulators, IR-sensitive switches, and light-triggered actuation components.
The results of this work show that QIRT is a strong, non-destructive quantitative method for measuring the inherent photothermal characteristics of natural dye materials. The approach shown here makes it easy to find dye candidates that have both excellent thermal stability and good optical-to-thermal conversion. These traits make them good candidates for photonic devices that are eco-friendly, cheap, and work well. The study also provides the framework for future integration of thermal modeling and material optimization methodologies targeted at furthering the development of sustainable photothermal components inside current photonic technologies.
