Antimony Thin Film as a Robust Broadband Saturable Absorber

Antimony shows unique electrical, optical response with the reduced dimension. Herein, the antimony thin film has been grown by vapor deposition method with a thickness of 12.8 nm, and its broadband nonlinear saturable absorption properties have been observed and characterized within the spectral range from 800 to 1930 nm. With the help of the antimony thin film, a Q-switched fiber laser with a pulse duration of 983 ns and a highly stable femtosecond fiber laser with pulse duration of 753 fs have been delivered from an Er
³⁺
-doped fiber laser. Furthermore, by incorporating the antimony thin film into an Er
³⁺
-doped fluoride fiber laser, stable Q-switched mid-infrared pulses with a pulse duration of 824 ns have been obtained. Our experimental results clearly highlight the promise of antimony thin film as a robust broadband optical signal processing component.