Performance investigation of erbium-doped fiber laser based on cadmium chloride hydrate saturable absorber

In this work, we have demonstrated passive Q-switched and mode-locked erbium-doped fiber lasers (EDFLs) by using metal salt of cadmium chloride hydrate (CdCl 2 .xH 2 O) as a saturable absorber (SA). The mechanical exfoliation method was utilized to fabricate the CdCl 2 .xH 2 O-SA. The fabricated SA showed a modulation depth of 20% with a saturation intensity of 80 mW/cm 2 . At a pump power of 167 mW, the proposed Q-switched laser operated at 1542 nm with a maximum repetition rate of 127 kHz and a narrowest pulse width of 1.76 µs. The maximum output power was 23 mW with a signal to noise ratio (SNR) of 76 dB. On the other hand, the mode-locked pulses were generated within a pump power range of 91–167 mW, achieving a repetition rate of 990 kHz. The maximum pulse energy and output power were 7.3 nJ and 7.2 mW, respectively. The SA film demonstrated reliability and simplicity in the fabrication process.