Study of point defects created by high-intensity ultrashort pulse laser in YLF crystals

摘要

In this work we report the creation of color centers in LiF and YLF crystals by high intensity, ultrashort laser pulses. We used pure and Tm~(3+) and Oxygen doped samples, all irradiated with a Ti:Sapphire CPA laser system and also with electron beam, at room temperature. In both kinds of irradiations the production of photochromic damages and color centers that have absorption bands in UV and visible range was observed. A comparison between the two kinds of irradiation was done and the involved processes are described in this paper. F_2~+ stable centers were produced by the ultrashort laser pulses irradiation in contrast to the well-known, short lived centers produced by electron beams, and a mechanism was proposed to explain the observed stability.