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Cadmium oxide (CdO) has recently attracted attention as a material with controllable properties tailored for optoelectronic and nanophotonic devices due to its superior mobility. However, its potential application in near-infrared (NIR) remains to be explored. In this work, we demonstrate that the epsilon-near-zero (ENZ) wavelength and nonlinear optical properties of CdO films can be effectively tuned by Mo doping. The results show that Mo doping increases the electron concentration as well as improve the crystalline quality of CdO. With increasing Mo doping, we achieve blueshifts of the ENZ wavelength from 2.89 to 1.56 μm. The nonlinear absorption (NLA) behavior at 1550 nm changes from reverse saturable absorption to saturable absorption with increasing Mo content. Moreover, significant improvement in NLA performance with nonlinear absorption coefficient β = −72 cm/GW is observed at the highest doping content. Our work shows that doped CdO films with tunable optoelectrical and nonlinear optical properties can be an ideal candidate for optoelectronic and nanophotonic application in the NIR region. [ABSTRACT FROM AUTHOR]

The laser-induced damage (LID) response of multilayer dielectric gratings (MDGs) to transverse magnetic (TM) and transverse electric polarization was investigated based on polarized-independent MDGs. It was found that TM-polarized MDGs have the superiority of a high LID threshold, low sensitivity to laser excitation strength, low response to damaged structure, and reduced LID growth speed and dynamics. These results provide a strong motive to preferentially develop and mount TM-polarized MDGs in the next generation of high-intensity picosecond-petawatt laser systems. [ABSTRACT FROM AUTHOR]

Laser polishing efficiently reduces the surface roughness of die steel, but at the same time, residual tensile stress is induced on the surface, leading to crack initiation and propagation. The present study induces residual compressive stress on the laser-polished surface of Cr12 steel by laser shock peening. The surface residual stress of samples, which underwent different treatments, is measured and compared. The experimental results show that laser shock peening effectively eliminates the residual tensile stress generated by laser polishing. The compressive residual stresses of the laser-polished samples subjected to laser shock peening with 3, 6, and 9 J energies are 114.5, −138.5, and −209.5 MPa, respectively. Moreover, the surface roughness, microhardness, and microstructure evolution of the laser-polished surface with laser shock peening are investigated. [ABSTRACT FROM AUTHOR]