Density functional theory investigation on formation of nanoscale PbS materials and its fabrication in silica optical fiber via atomic layer deposition

•Formation mechanisms for PbS nanomaterials grown on silica substrate are studied by DFT.•PbS are doped into the fiber core via ALD, with nanostructure confirmed by HRTEM.•PbS-doped fiber exhibits fluorescence property at 1060–1370 nm with 1064 nm pumping.•PbS-doped fiber amplifier exhibited a signal gain as 9.4 dB at 1310 nm.