Improving the stability of vanadium aluminum carbide (V 2 AlC) based saturable absorbers for Er-doped fiber lasers

Abstract The vanadium aluminum carbide (V 2 AlC) has been examined as a saturable absorber (SA) for the Q-switching of an erbium-doped fiber laser (EDFL). Three configurations were used to test the MAX phase material (V 2 AlC) as a mesh powder SA, and thin films prepared by pulsed laser deposition (PLD) with the thicknesses of 500 nm and 1 μ m. The V 2 AlC mesh powder SA achieved a maximum repetition rate of 90.23 kHz and a minimum pulse duration of 4.95 μ s by varying the pump power from 19.36 to 172.48 mW. In contrast, PLD thin film with a thickness of 500 nm achieved the highest repetition rate of 84.17 kHz and a minimum pulse duration of 6.15 μ s when the pump power is increased from 19.36 to 129.36 mW. Similarly, PLD thin film with a thickness of 1 μ m achieved a maximum repetition rate of 117.34 kHz and a minimum pulse duration of 3.9 μ s when the pump power is increased from 19.36 to 273.24 mW. The comparison for peak power and pulse energy, mesh powder has a maximum pulse energy of 7 nJ and peak power of 0.91 mW, on the other hand, for PLD thin film having a thickness of 500 nm, the maximum pulse energy was 33 nJ and peak power of 7.3 mW. Similarly, maximum pulse energy of 41 nJ and peak power of 14.95 mW were measured for the thin film of thickness 1 μ m prepared by PLD. This is the first study that used a V 2 AlC thin film of different thicknesses grown by PLD and demonstrated the passive Q-switching, along with a detailed method for the measurement of the stability of EDFL.