Ultrafast laser pulses generation by using the ultrasmall topological semimetal TaN quantum dots

Abstract

The synthesis of ultrasmall tantalum mononitride (TaN) quantum dots (QDs) is achieved using a straightforward liquid exfoliation technique, starting from bulk TaN. This work presents the evidence of generating an ultrafast laser by employing TaN QDs as a saturable absorber (SA) within an Erbium-doped fiber laser for the first time. Stable ultrashort pulses are generated, exhibiting a center wavelength of 1566.92 nm, a pulse duration of 713 fs, and a cavity repetition rate of 41.39 MHz. Furthermore, the utilization of TaN QDs as an SA in the device exhibits good nonlinear saturable absorption properties with a modulation depth of 1.37%. Those results presented in this study add to the existing literature on the investigation of nonlinear optical characteristics of ultrasmall QDs and also highlight the potential for future development in ultrafast photonic technology.