ABSTRACT
This chapter identifies different ultra-short laser–matter interaction regimes. These regimes are separated by the intensity, pulse duration, nature of a target beam position on the target and the focusing conditions. The chapter presents the description of the major tool, laser beam, and the studied subject—metal and dielectric solids. From the quantum viewpoint, a laser beam is the flow of photons. Quantum mechanical description of photons beam is necessary when the number density of photons is less than one photon per cubic wavelength. The initial spectral structure of the pulse assumed to be well defined with the central frequency and the band’s width corresponding to the pulse duration. The criterion of the short pulse/matter interaction mode is the contrast ratio of the intensity in the main pulse to the intensity of the pre-pulse. Laser–matter interactions are performed in the different relative positions of the tool and material.
