2. Principle of LIBS spectroscopy

LIBS spectroscopy is atomic emission spectroscopy using laser-induced plasma. The acronym LIBS stands for Laser-Induced Breakdown Spectroscopy, but the technique is also known as LIPS for Laser-Induced Plasma Spectroscopy. It is one of a number of spectroscopy techniques based on the use of a laser. . Recent works describe in detail the physical principles of the technique and its applications. A brief description follows.

When an intense laser pulse is focused on the surface of a solid material, the laser fluence may exceed the value corresponding to the ablation threshold. In this case, the laser-induced ablation generates a crater on the surface of the material, accompanied by the creation of a plasma, i.e. an ionized gas containing the chemical elements stripped from the material.

The ejected matter...