Few-layer Ti3C2Tx (T = O, OH, or F) saturable absorber for a femtosecond bulk laser

Few-layered titanium carbide (Ti3C2Tx), a novel two-dimensional (2D) Van der Waals material in the MXene family, was fabricated with a liquid-phase method and applied as a saturable absorber for a continuous-wave mode-locked femtosecond bulk laser. Pulses as short as 316 fs with a repetition rate of 64.06 MHz and maximum output power of 0.77 W were achieved at the central wavelength of 1053.2 nm, demonstrating the first known, to the best of our knowledge, application of MXene in an all-solid-state laser. Considering the flexible band gap for different surface functional groups of Ti3C2Tx, these results may promote the development of ultrafast photonics and further applications of 2D optoelectronic layered materials in the infrared and mid-infrared regions. (C) 2018 Optical Society of America