A graphene-based mode-locked nano-engineered zirconia-yttria-aluminosilicate glass-based erbium-doped fiber laser

We demonstrate a simple, compact and low cost graphene-based mode-locked nano-engineered erbium-doped zirconia-yttria-aluminosilicate (ZYA-EDF) glass-based fiber laser. The fiber preform in a quaternary glass host of silica-zirconia-yttria-aluminum was made through the modified chemical vapor deposition (MCVD) process followed by the solution doping technique. The core glass is made of 0.40 mol% of Al2O3, 3.0 mol% of ZrO2 and 0.25 mol% of Er2O3, which give rise to a peak absorption of 30.0 dB m(-1) at 978 nm and a fluorescence lifetime of 10.65 ms. Such a doping host provides the high concentration of erbium ions of 4500 ppm without any clustering. Such an active fiber was used as a gain medium for an ultra-fast femtosecond fiber laser, mode locked by a graphene oxide (GO) saturable absorber. This paper describes geometrical and optical characterization of the nano-engineered glass-based erbium-doped optical fiber (ZYA-EDF) as well as the performance of the mode-locked femtosecond laser based on the developed fiber. The all-anomalous cavity laser generated soliton pulses with 8.5 nm bandwidth, 50 MHz repetition frequency and nearly transform-limited 400 fs duration at 1561 nm center wavelength using a new class of EDF.