Watt-level broadband PM Tm-doped fiber amplifier for the 1750–1910 nm window

Abstract

We report broadband experimental and simulated performance of a single-clad polarization-maintaining (PM) thulium-doped fiber amplifier (TDFA) optimized for operation in the 1750–1910 nm wavelength band. With the two-stage amplifier architecture, a maximum output power of 2.4 W was obtained at 1850 nm for 7.0 W of launched pump power at 1567 nm, with a corresponding optical-to-optical efficiency of 31.4 %. The measured polarization extinction ratio (PER) was larger than 22.6 dB, and the long-term power stability exhibited a peak-to-peak variation of 2.4 %. By employing a tunable seed laser covering the 1750–1910 nm wavelength range, we measured a maximum output power level of 2.38 W with an optical signal-to-noise ratio (OSNR) greater than 53 dB/0.1 nm. Our simulations are in good agreement with the experimental data over the whole 160 nm operating spectral bandwidth.