Experimental setup for laser damage measurements. HR: High reflective mirror; Sh: mechanical shutter; BS: wedged beam splitter; W: half wave plate; P: thin film polarizer; Py1: pyroelectric detector; Py2: pyroelectric detector for calibration; ND: set of multidieletric neutral density filters; L: focusing lens; M: Nomarski microscope with camera; S: sample; F: infrared filter; BP: beam profiler; SSA: single shot autocorrelator; CCD: cooled CCD camera. This last instrument is part of a high-resolution energy detection arm that will be described in Sec. III.
Autocorrelation trace of the femtosecond laser.
Spectral profile of the femtosecond laser.
Laser beam profile on the focus plane.
Linear behavior of the measured integral with the energy send on the sample.
Example of a CCD camera measurement. The two white squares represent the selected areas for the determination of the integral value.
Evolution of the normalized integrals with time. Inset: plot of the integral obtained on spot 1 as a function of the integral obtained on spot 2; the line is a linear fit of the data.
Calibration of the maximal pixel value on the beam image as a function of the corresponding fluence. The linearity is evidenced by the line.
Laser damage probabilities measured on the fused silica substrate. Test conditions: 50 tested sites by fluence and 20 different fluences (1000 sites have been tested), pulse duration of 520 fs, and the laser parameters described in Sec. II.
Laser damage probabilities measured on the hafnia coating. Test conditions: 50 tested sites by fluence, pulse duration of 520 fs, and the laser parameters described in Sec. II.
Laser damage thresholds of single layer materials deposited on fused silica samples as a function of the measured bandgap. The reported LIDT is the internal threshold fluency in J/cm2 (see text).
Transmittance and reflectance curves of a Ta2O5 single layer on a silica substrate.
Variations of the different laser parameters, expressed in terms of standard deviation at 1σ.
Gap values obtained on a Ta2O5 single layer.
n (at 1030 nm), t, and Gap values obtained on Ta2O5 single layers of different thicknesses with the Tauc-Lorentz model.
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