The Damage Threshold of Multilayer Film Induced by Femtosecond and Picosecond Laser Pulses

Abstract

Laser-induced damage threshold (LIDT) is an essential factor in measuring the anti-laser damage of optical films. The damage threshold and morphology of the Ta2O5/SiO2 multilayer film prepared by electron beam evaporation were studied by femtosecond (50 fs) and picosecond (30 ps) laser irradiations. The results showed that the LIDT of the film was 1.7 J·cm−2 under the femtosecond laser. The damage morphology developed from surface damage to a clear layered structure, and the outline has become more transparent and regular with an increase in the laser fluence. Under the picosecond laser irradiation, the LIDT of the film was 2.0 J·cm−2. The damage morphology developed from small range to thin film layer separation, and the outline changed from blurry to clear with an increase in laser fluence. Therefore, the LIDT of the film decreased with a decrease in the laser pulse width.

Femtosecond laser ablation evolution of ultrahard double-layer films

“…Aleksander G. Kova Currently cević et al [11] studied the micro/nano structure and formation effect of femtosecond laser on the ablation of aluminum monolayer film on silicon substrate and multilayer film composed of five aluminum/titanium bilayer films. Yunzhe Wang et al [12] have studied the damage thresholds and morphologies of Ta2O5/SiO2 multilayers for femtosecond and picosecond lasers. S. Petrović et al [13] studied femtosecond laser modification of single and complex nickelpalladium samples and compared the surface nanostructures.…”

A Dichroic Beamsplitter for the Laser Protection of Infrared Detectors

“…Among them, Ta 2 O 5 films deposited by ion-assisted electron-beam deposition (IAD) and HfO 2 films deposited by EBE have relatively high LIDTs [17][18][19][20][21]. However, compared with EBE-HfO 2 , IAD-Ta 2 O 5 has better thermal and chemical stability and smaller absorption in the MIR spectral range and can therefore be widely used in many fields [22,23].…”

Damage Characteristics of Aluminum-Coated Grating Irradiated by Nanosecond Pulsed Laser

“…Damage to thin-film materials by nanosecond pulsed lasers involves complex physical mechanisms, such as impurity-induced phase explosion [7,8], phase transition-induced mass removal [9], plasma-induced plasma expansion [10], plasma shielding [11], and shock wave effects [12][13][14]. To date, with the improvement of laser technology, researchers have studied the damage mechanisms and damage thresholds of various lasers acting on different gratings [15][16][17], including those of continuous lasers on multilayer dielectric film gratings [18][19][20], and those of nanosecond pulsed lasers and ultrafast lasers acting on gold, multilayer dielectric, and hybrid multilayer dielectric film gratings [21]. However, aluminum-coated gratings are also widely used in spectrometers, aperture cameras, and detection devices because of their low cost, high practicability, stable reliability, and high diffraction efficiency, but there are few reports on the damage caused to aluminum-coated gratings irradiated by 1064 nm nanosecond pulsed lasers.…”

“…Moreover, previous research has generally focused on the influence of the laser parameters on grating damage, such as wavelength [22], pulse width [15], spot [23] and pulse accumulation [24] effects; the differences in laser damage caused by different grating structure characteristics [25] such as the substrate material, the thickness of the film, the stacking of the films, and the manufacturing process; and the damage induced by impurities, defects [26], and contamination [27]. Most of the research methods have been based on experiments, with a lack of reports on the use of simulation models to predict the LIDT of metal gratings irradiated by nanosecond lasers.…”