Sb2Te3 topological insulator for 52 nm wideband tunable Yb-doped passively Q-switched fiber laser

Topological insulator Sb2Te3 has the advantage of broadband saturable absorption from the visible to the infrared bands.Herein,the two-dimensional material Sb2Te3 saturable absorber(SA)of the topological insulator family was first applied experimentally in a wideband tunable passively Q-switched Yb-doped fiber laser.High-quality Sb2Te3 crystals were synthesized by the flux zone method.The Sb2Te3 SA with fewer layers was further prepared via a modified mechanical exfoliation procedure.Meanwhile,stable wavelength-tunable passive Q-switching pulse operation was obtained in a Yb-doped fiber ring cavity based on the Sb2Te3 SA,where the central wavelength can be continuously tuned from 1040.89 to 1092.85 nm.Results suggest that Sb2Te3 has wideband saturable absorption properties,and that the tunable pulse laser can provide a convenient and simple source for practical applications.