Atomic and Ionic Luminescence of Dysprosium at Sonolysis by a Single Moving Bubble of a Colloidal Suspension of Nanoparticles Containing Dysprosium Chloride

Abstract

As part of research on the development of sonoluminescent spectroscopy, atomic and ionic singlebubble sonoluminescence of dysprosium was first recorded in the mode of bubble movement in a standing ultrasonic wave in a colloidal dodecane suspension of SiO₂ nanoparticles containing DyCl₃. In the spectrum of this sonoluminescence with a resolution of ∆λ = 1 nm, the Dy, Dy⁺ lines in a region of 350–450 nm were recorded together with the molecular SiO lines, due to the entry of nanoparticles into the bubble during sonolysis of the suspension and subsequent collisional excitation of emitters in the bubble plasma. At a spectral resolution of ∆λ = 10 nm, Dy3⁺ luminescence bands with maxima at 477 and 570 nm, which appear by the same excitation mechanism, were recorded. By comparing the experimental and temperature-dependent calculated spectra of Dy, Dy+, the electron temperature of T_e = 7000±300 K was found in the nonequilibrium plasma that occurs during bubble collapse, where dysprosium atoms and ions emit light.