High average power parametric wavelength conversion at 3.31-3.48 m in MgO:PPLN

We present results of high average power mid-infrared (mid-IR) generation employing synchronized nanosecond pulsed ytterbium and erbium fiber amplifier systems using periodically poled lithium niobate. We generate greater than 6 W of mid-IR radiation tunable in wavelength between 3.31-3.48 μm, at power conversion efficiencies exceeding 75%, with near diffraction limited beam quality (M² = 1.4). Numerical modeling is used to verify the experimental results in differing pump depletion regimes.