Supplement Number 1

See the supplementary material for experiment and simulation details, calculation methods, SEM image, simulated absorption spectra, detection limit of LN/Ag, SERS signals from five batches of substrates, R6G SERS intensity over time, working mechanisms of pyroelectric effect, pyroelectric carrier and voltage, SERS spectra at different heating and cooling rates, SERS signals of MB and AM molecules, SERS signals of R6G on FLN/Ag substrate, SERS signals from FLN/LIPSS/R6G/Ag substrate, absorption spectra and SERS intensities at different temperatures, schematic diagrams of CM for MB, AM and CV molecules, detection limit of 4-ABT and CV.