Nonlinear optical response of reflective MXene molybdenum carbide films as saturable absorbers

Molybdenum carbide (Mo₂ C) is a two-dimensional (2D) MXene material which makes it a promising photoelectric material. In this study, reflective type MXene Mo₂ C thin films were coated on a silver mirror by a magnetron sputtering method and were subsequently used in a passively Q-switched solid-state pulsed laser generator at the central wavelengths of 1.06 and 1.34 µm, respectively. The fabricated thin films of reflective type MXene Mo₂ C exhibited large modulation depth of 6.86% and 5.38% at the central wavelengths of 1064 and 1342 nm, respectively. By inserting the Mo₂ C saturable absorbers (SAs) into V-shaped Nd:YAG laser, short pulses were generated having a pulse duration, pulse energy, and average output power of 254 ns, 2.96 µJ, and 275 mW, respectively, at a wavelength of 1.06 µm. Similarly, shorter laser pulses were obtained in Nd:YVO₄ laser at 1.34 µm. Our results illustrated potential of the 2D MXene Mo₂ C films for laser applications.