Summary: This is the collection of datasets used to plot the line art figures for the journal paper “Extended Infrared Absorption in Nanostructured Si Through Se Implantation and Flash Lamp Annealing”. Methods: The experimental and calculation methods for generating the datasets are described in the original paper and in the supplementary materials. File Description: The filenames for all files match the figure captions from the original paper and supplementary materials. Each file represents a specific plot, with all files provided in CSV format. Each column in the file represents a set of variable data. The datasets corresponding to each curve can be identified by comparing the first-row header information with the figure legend. Credit: When using the dataset/figures, please cite the original paper as: Radfar, B., Liu, X., Berencén, Y., Shaikh, M.S., Prucnal, S., Kentsch, U., Vähänissi, V., Zhou, S. and Savin, H. (2024), Extended Infrared Absorption in Nanostructured Si Through Se Implantation and Flash Lamp Annealing. Phys. Status Solidi A 2400133. https://doi.org/10.1002/pssa.202400133