Measuring thermal effects in femtosecond laser-induced breakdown of dielectrics

F Ladieu (1, 2) , Ph Martin (2) , S. Guizard (3)

1 SPHYNX - Systèmes Physiques Hors-équilibre, hYdrodynamique, éNergie et compleXes
2 SPEC - UMR3680 - Service de physique de l'état condensé
3 LSI - Laboratoire des Solides Irradiés - Irradiated Solids Laboratory

A quartz sample was submitted to femtosecond laser pulses with fluences up to 6×Fc,6×Fc, where FcFc is the laser-induced breakdown fluence. A series of microthermocouples, deposited onto the surface, was used to measureheatings at the millisecond scale, at typically 50 μm from the laser impact. By using both the heat propagation equation and the Helmholtz equation to get the energy absorption profile, we estimate a minimum value of the temperature reached in the center of the crater. Even very close to Fc,Fc, this temperature is found to be ≳3000 °C,≳3000 °C, proving that heating effects play a major role in the breakdown of dielectrics.

Domaines: Physique [physics]

F Ladieu, Ph Martin, S. Guizard. Measuring thermal effects in femtosecond laser-induced breakdown of dielectrics. Applied Physics Letters, 2002, ⟨10.1063/1.1498147⟩. ⟨cea-01395453⟩