Vibronic Transitions of Atomic Bubbles in Condensed 4He

Abstract

Laser spectroscopy of atomic dopants can be used as a tool for the investigation of elementary excitations in quantum fluids and solids. Here we present results of a laser-spectroscopic study of transition-metal (Au, Cu) atoms in liquid and solid 4He. In particular we observe transitions of inner shell electrons that have not been studied before. Such transitions are weakly perturbed by the interaction with the helium matrix and display a characteristic structure composed of a sharp zero-phonon line and a relatively broad phonon wing.