Mapping Mid-Infrared Dispersion Landscape onto Near-Infrared and Visible through Filamentation of Laser Pulses at 3.9 μm in Air

Nonlinear self-channeling (filamentation) of intense, ultrashort laser pulses in air has numerous potential applications ranging from remote sensing in the atmosphere to lightning control [1]. Recent progress in optical parametric chirped-pulse amplification (OPCPA) technology pushes the investigations of filamentation into short-wave infrared [2] and mid-wave infrared [3] regimes. At longer wavelengths, the propagation dynamics is affected by the presence of windows of anomalous dispersion due to the trace constituents of air [4,5]. Multiple odd harmonics of the infrared driver pulse can be easily detected and analyzed.