In this study, we investigate the ultrafast dynamics of free electrons in skin-like tissue media, stimulated by laser pulses with durations between 50 fs and 100 fs. Our analysis is based on a rate-equation approach for the evolution of free electron density under different laser pulse durations. The simulated electron densities are then used to calculate the time-dependent change in reflectivity, , via a Drude-based dielectric function model and Fresnel equations for normal incidence. This enables us to assess the transient optical properties of tissue equivalents during and after ultrafast electronic excitation. The results highlight characteristic thresholds for carrier generation and show how pulse parameters influence the magnitude and temporal profile of . The presented approach offers a framework for understanding and predicting ultrafast reflectivity changes in tissue-like media, which can be useful for laser-based diagnostics, ultrafast imaging, and controlled photothermal treatments.
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