Nanosecond-to-femtosecond laser-induced breakdown in dielectrics

2019-10-10 10:36:54

breakdown damage laser ionization avalanche

责任者: Stuart, B.C.;Feit, M.D.;Herman, S.;Rubenchik, A.M.;Shore, B.W.;Perry, M.D. 单位: Lawrence Livermore Nat. Lab., CA, USA 来源出处: Physical Review B (Condensed Matter)(Phys. Rev. B, Condens. Matter (USA)),1996/01/15,53(4):1749-61 摘要: We report extensive laser-induced damage threshold measurements on dielectric materials at wavelengths of 1053 and 526 nm for pulse durations ranging from 140 fs to 1 ns. Qualitative differences in the morphology of damage and a departure from the diffusion-dominated τ1/2 scaling of the damage fluence indicate that damage occurs from ablation for τ⩽10 ps and from conventional melting, boiling, and fracture for τ>50 ps. We find a decreasing threshold fluence associated with a gradual transition from the long-pulse, thermally dominated regime to an ablative regime dominated by collisional and multiphoton ionization, and plasma formation. A theoretical model based on electron production via multiphoton ionization, Joule heating, and collisional (avalanche) ionization is in quantitative agreement with the experimental results 关键词: avalanche breakdown;electric breakdown;laser beam effects;nanosecond-to-femtosecond laser-induced breakdown;dielectrics breakdown;morphology;ablation;melting;boiling;fracture;decreasing threshold fluence;electron production;multiphoton ionization;Joule heating;collisional avalanche ionization;avalanche ionization;1053 nm;526 nm;10 ps;140 fs to 1 ns