Two-dimensional (2D) materials with potential applications in photonic and optoelectronic devices have attracted increasing attention due to their unique structures and captivating properties. However, generation of stable high-energy ultrashort pulses requires further boosting of these materials’ optical properties, such as higher damage threshold and larger modulation depth. Here we investigate a new type of heterostructure material with uniformity by employing the magnetron sputtering technique. Heterostructure materials are synthesized with van der Waals heterostructures consisting of ${\mathrm{MoS}}_2$ and ${\mathrm{Sb}}_2{\mathrm{Te}}_3$. The bandgap, carrier mobility, and carrier concentration of the ${\mathrm{MoS}}_2\text{-}{\mathrm{Sb}}_2{\mathrm{Te}}_3\text{-}{\mathrm{MoS}}_2$ heterostructure materials are calculated theoretically. By using these materials as saturable absorbers (SAs), applications in fiber lasers with $Q$-switching and mode-locking states are demonstrated experimentally. The modulation depth and damage threshold of SAs are measured to be 64.17% and $14.13\mathrm{J}/{\mathrm{cm}}^2$, respectively. Both theoretical and experimental results indicate that ${\mathrm{MoS}}_2\text{-}{\mathrm{Sb}}_2{\mathrm{Te}}_3\text{-}{\mathrm{MoS}}_2$ heterostructure materials have large modulation depth, and can resist high power during the generation of ultrashort pulses. The ${\mathrm{MoS}}_2\text{-}{\mathrm{Sb}}_2{\mathrm{Te}}_3\text{-}{\mathrm{MoS}}_2$ heterostructure materials have the advantages of low cost, high reliability, and suitability for mass production, and provide a promising solution for the development of 2D-material-based devices with desirable electronic and optoelectronic properties.