Passively mode-locked fiber lasers at 1039 and 1560 nm based on a common gold nanorod saturable absorber

Abstract

We demonstrated passively mode-locked ytterbium and erbium doped fiber lasers operating at 1039 and 1560 nm by using a common gold nanorods (GNRs) saturable absorber (SA). The GNRs with designed aspect ratios were mixed with sodium carboxymethylcelluose to form the GNRs SA film. The film had broadband longitudinal SPR (surface plasmon resonance) absorption from 800 to 1800 nm. By inserting the same film into a ytterbium or erbium doped fiber laser cavity pumped by a 980 nm laser diode, stable passively mode-locked laser operation at 1039 or 1560 nm was achieved for a threshold pump power of ~100 or ~70 mW, respectively. The pulse width, the output power, and the repetition rate of the 1039 nm mode-locked laser were 460 ps, 1.47 mW, and 43.5 MHz for a pump power of ~110 mW, respectively. The corresponding output parameters of the 1560 nm mode-locked laser were 2.91 ps, 2 mW, and 35.6 MHz for a pump power of ~74 mW, respectively. Our results showed that one GNRs SA could be used for constructing broadband mode-locked lasers.