Determination of a dose-like curve for active colour centres produced in LiF single crystals by ultrashort high intensity laser pulses and a preliminary investigation of their spectral and spatial properties by confocal and atomic microscopies

Abstract

In this paper, the spatial and spectral properties of colour centres produced in LiF single crystals by ultrashort high intensity laser pulses are reported. The emission spectra of the centres were measured conventionally and also by confocal microscopy. A large amount of F centres that gave rise to aggregates such as F2, F4, F+2 and F+3 could be identified, showing a microscopic homogeneous distribution. The coloured surfaces were also spatially characterized by atomic force microscopy, and the images show the presence of defects on the modified surface. The formation of micrometric and sub-micrometric structures was observed and related to filamentation processes.