Ta2NiSe5 nanosheets as a novel broadband saturable absorber for solid-state pulse laser generation

Two-dimensional (2D) ternary chalcogenides have attracted great attentions because of their novel chemical and physical properties arising from the synergistic effect stoichiometric variation with additional third element compared binary counterparts. Here, high-quality 2D tantalum nickel selenide (Ta2NiSe5) nanosheets are successfully fabricated by a liquid-phase exfoliation (LPE) method. The ultrafast excited carrier relaxation time nonlinear optical absorption response investigated reveal that prepared Ta2NiSe5 excellent broadband saturable properties, which further illustrated three passively Q-switched (PQS) all-solid-state lasers operating at 1.0, 2.0 2.8 µm nanosheet-based absorber (SA). Furthermore, mode-locked laser operation pulse width as short 356 fs is also realized 1.0 µm. This work not only demonstrates proprieties modulation performance Ta2NiSe5, but paves way for exploring photonic optoelectronic chalcogenide materials.