Dual fiber laser pumped tunable mid-infrared laser source with high speed modulation

We demonstrated a mid-infrared source architecture based on difference frequency generation of two tunable pulsed fiber laser sources. The mid-infrared source is tunable from 2910 nm to 3520 nm with up to 250 mW average power. The timing between pumps is controlled electronically to achieve modulation rates exceeding 10 kHz with over 35 dB extinction ratio. Spatially, the mid-infrared beam has a M² value of 1.06 and 1.08 (across its principal axes). Spectrally, the linewidth is 0.6 nm, with a wavelength accuracy of ± 0.3 nm.