How does Laser Induced Breakdown Spectroscopy (LIBS) work?

LIBZ Technology Diagram

1. A pulsed laser is focused on a sample to break down (ablate) a small volume of it. The interaction of the ablated mass with the laser generates a high temperature plasma plume which contains the sample’s excited atoms and ions.

2. As the plasma starts to cool, the electrons of the excited atoms and ions fall back down to their ground states. As they return to their ground states, light is emitted from the plasma and collected for the spectrometer.

3. The spectrometer separates all light emissions with high resolution optics to be detected by the advanced charged couple device.

The Z is based on a well-established technology called laser induced breakdown spectroscopy (LIBS) or LIBZ as we like to call it.  With LIBS, a laser is fired at a sample, heating it almost instantaneously and creating an electron plasma.  As the plasma cools after about 1 us, the electrons return to the atoms that constitute the sample, emitting light at various discrete wavelengths.  The spectrometer resolves the wavelengths and the processor determines elements present and concentrations. LIBZ is an optical technique, not x-ray.  The measured light is in the UV, visible and NIR spectral region.  Therefore many more elements can be analyzed compared to portable XRF.  Elements hydrogen (H) to sodium (Na) may be measured by the Z, but cannot be measured by portable XRF.  This includes critical elements like C, Li, Be, B, Na and others.  The Z measures elements Mg, Si, Al at much lower detection limits, compared to portable XRF due to the optical nature of the technology. Laser-induced Breakdown Spectroscopy (LIBS) offers an alternative technique to both handheld XRF and spark OES for the analysis of a broad range of elements and sample types.  In the LIBS process, a plasma is creat-ed at the material surface, as in spark optical emission spectroscopy (OES).  Spectral lines from the various ele-ments present are measured as the plasma cools. The wavelength of specific lines reveals the elements pres-ent, and the intensity of the light at a given wavelength is related to the concentration of each element.