Third-order nonlinear optical responses and carrier dynamics in antimonene

Antimonene (Sb), a novel 2D crystalline, has recently received intense attention from optoelectronic communities, due to its enticing physical and chemical properties. Here we systematically investigate the broadband third-order nonlinear optical properties and carrier dynamics in antimonene. Efficient saturable absorption effect was observed at different wavelengths, indicating the use for broadband ultrafast laser generation. The nonlinear refractive indexes were characterized to be (2.55 ± 0.23) × 10 −14  cm 2 /W and (7.88 ± 0.37) × 10 −15  cm 2 /W at 800 nm and 1500 nm, respectively. Photoinduced carrier dynamics are investigated by a non-degenerate transient absorption spectrometer. Fast recovery processes were observed in antimonene and suggesting a high optical modulation speed to 500 GHz.