Generation of Tunable MIR/LWIR Femtosecond Pulses by Combination of SRS and DFG

A number of industrial and scientific applications require high-energy pulses in the mid-infrared (MIR) or long-wave infrared (LWIR) spectral regions [1]. Energetic ultrashort MIR/LWIR laser pulses are typically generated in traveling wave optical parametric amplifiers (OPAs), seed for which is produced by either intra-pulse difference frequency generation (DFG) starting from a single broadband near-infrared (NIR) pulse [2] or via inter-pulse DFG between parametrically down-converted in an OPA signal pulses and pulses from NIR pump lasers [3].