Fig. 1. Schematic diagram of the proposed MDLM design.

Fig. 2. Schematic diagram of the deposition process of MDLM coating.

Fig. 3. Microstructure and optical property of the pure monolayer, nanolaminate, and mixture coatings. (a) XRD spectra, (b) transmittance, and (c) optical bandgap versus n of HfO2 monolayer, Al2O3 monolayer, HfO2−Al2O3 nanolaminate, and mixture coatings. (d) Surface figure change (ΔPower) caused by the HfO2−Al2O3 nanolaminate and mixture coatings.

Fig. 4. Dispersion curves of refractive indices of HfO2 monolayer, Al2O3 monolayer, and HfO2−Al2O3 mixture coatings.

Fig. 5. Elemental percentage profiles from the high-n layer to the low-n layer.

Fig. 6. Microstructure and optical property of the TDLM and MDLM coatings. (a) XRD spectra. (b) Transmittance (left: incident angle at 0°; middle: incident angle at 45°, p-polarized light) and reflectance spectra (right: incident angle at 45°, s-polarized light). (c) Surface figures of the samples before and after coating. (d) Surface and cross-section morphologies after the scratch test. (e) Single-pulse damage probability as a function of the input fluence.

Fig. 7. Damage morphology imaged by SEM and the depth profile of the marked area measured by FIB. (a)–(d) Damaged sites and (e)–(h) schematic diagram of the damage morphologies after irradiation of an s-polarized 532 nm laser. (i) and (j) Plasma scald induced by s-polarized 532 nm laser in MDLM coating.

Fig. 8. Damage morphology imaged by SEM and the depth profile of the marked area measured by FIB. (a) and (b) Full field-of-view of the damaged area. (c)–(i) Typical damaged sites marked with asterisks. (j)–(m) Schematic diagram of the damage morphologies after irradiation of a p-polarized 1064 nm laser.

Fig. 9. EDS characterized chemical composition of the damaged site of the TDLM coating and MDLM coating induced by 1064 nm p-polarized laser.

Fig. 10. Simulated laser-induced temperature rises in TDLM and MDLM coatings.

Table 1. Design Information and Extracted Thickness of the Nanolaminate Coatings^a

Table 2. Extracted Defect Parameters