laserdesorpsjon

Laserdesorption is a process where a pulsed laser beam is used to remove material from a solid or liquid surface. When the laser light interacts with the surface, the energy is absorbed by the material, causing a rapid increase in temperature and leading to the ejection of atoms, molecules, or clusters. This process is typically carried out in a vacuum or low-pressure environment to prevent re-condensation or reactions of the desorbed species.

The efficiency and characteristics of laser desorption depend on several factors, including the laser wavelength, pulse duration, energy density, and the properties of the target material. Different laser wavelengths can selectively target specific components within a sample, allowing for more controlled desorption. Short pulse durations are often preferred to minimize thermal diffusion into the bulk material, resulting in cleaner desorption with less fragmentation.

Laser desorption has found applications in various scientific fields. In mass spectrometry, it is used as an ionization source, particularly for large and non-volatile molecules that are difficult to ionize by other methods. Techniques like Matrix-Assisted Laser Desorption/Ionization (MALDI) are prominent examples. It is also employed in surface analysis, thin film deposition (pulsed laser deposition), and the study of material properties. The ability to desorb material with minimal damage and high spatial resolution makes it a valuable tool for analytical and preparative purposes.