Femtosecond filament-driven mid-IR lasing under plasma–chemical reaction in high-pressure mixture SF6 -H2 –Ar

A scheme of plasma–chemical mid-IR hydrogen fluoride (HF) lasing is proposed, in which electrons of femtosecond filament are produced in argon and give rise to a chain of plasma–chemical reactions occurring with SF6 and H2 added to the argon bath and resulting in the formation of vibrationally excited HF molecules. The conditions for the occurrence of amplified spontaneous emission and lasing in the range of 2.7–3 μm in a selected gas mixture at a total pressure of several atmospheres can be realized under the action of a femtosecond laser on Cr-forsterite with a wavelength of 1.24 μm. In numerical experiments, it was demonstrated that HF lasing energy at the level of 1.5 μJ are achievable for typical monofilament plasma parameters.