Spectroscopy of a laser plume arising under radiation of a ytterbium fiber laser

Abstract

The spectra of luminescence of plumes that occur near targets of Nd: Y₂O₃, YSZ, and Al₂O₃ when they are irradiated by pulses of a ytterbium fiber laser with a wavelength of 1.07 μm, duration of 1450 μs, and intensity of 0.4 MW/cm² are studied. Craters with a diameter of 400 μm and a depth of 600 μm appeared under such exposure in the targets. It is shown that the bands of the cation’s radicals of the targets, the intensities of which are distributed according to a law close to Planck’s law, predominate in the spectra of the plumes. On this basis, the temperature of the plumes was determined. It was about 2200–2280 K at the surface of the target, which is below the boiling temperature of the target due to cooling of the vapor during the passage of the deep laser crater.