Local growth of Ag-NP under CW laser irradiation at 514 nm. (a) Optical absorption spectra of a sample doped with silver nitrate in various conditions and a photograph of the ‘written’ sample after irradiation. (b) Corresponding TEM images showing Ag-NP of large dimensions. A magnification of certain NP shows lattice planes attributed to metallic Ag. (c) Another HRTEM image showing atom interplanar distances corresponding to Ag2O. (d) Optical absorption spectra obtained with the precursor Aghfacac.