Dataset to accompany the paper"Resonant Fully dielectric metasurfaces for ultrafast Terahertz pulse generation."The dataset is provided in a .mat format,. Separated into folders for each metasurface denoted in the paper. Then each file is labelled by by input wavelength of the laser. Each metasurface also has a power folder as measured by the opo. Each file is broken into two sets, the reading of the lock-in amplifier and the time axis.Inside the theoretical modelling folder is the .mat data for the theoretical modelling, separated by metasurface and then inside the file separated by energy, thz frequency and wavelength.</p