DFG-based mid-IR tunable source with 0.5 mJ energy and a 30 pm linewidth.

We report on a laser system based on difference frequency generation (DFG) to produce tunable, narrow-linewidth (<30), and comparatively high-energy mid-IR radiation in the 6.8 µm region. The system exploits a lithium thioindate () nonlinear crystal and nanosecond pulses generated by single-frequency Nd:YAG and Cr:forsterite lasers at 1064 and 1262 nm, respectively.

24 mJ Cr:forsterite four-stage master-oscillator power-amplifier laser system for high resolution mid-infrared spectroscopy.

We present the design of a Cr:forsterite based single-frequency master-oscillator power-amplifier laser system delivering much higher output energy compared to previous literature reports. The system has four amplifying stages with two-pass configuration each, thus enabling the generation of 24 mJ output energy in the spectral region around 1262 nm. It is demonstrated that the presented Cr:forsterite amplifier preserves high spectral and pulse quality, allowing a straightforward energy scaling.