Optical Absorption Spectra of EuAlO₃

Abstract

The absorption spectra of EuAlO₃ were measured in the frequency range, 17100–21500 cm⁻¹, in which the transitions from the ground state ⁷F₀ to the Stark components of the three lowest excited multiplets of ⁵D_J(J=0, 1, 2) states were observed. The spectral lines were assigned to the transitions to the crystalline-field split components of ⁵D_J(J=0, 1, 2) of Eu³⁺ ions with the C_s site symmetry. The crystalline field analysis of these lines was made by assuming the approximate site symmetry C_2v. The observed linewidths are 3–5 cm⁻¹ at 1.9°K and much broader than those in dilute YAlO₃:Eu³⁺. Furthermore, some of the lines seem to have two components with comparable intensity. The sources of these additional broadenings and structures of the lines are discussed. Many sharp and weak satellites were observed near the main lines. The origins of these satellites are also discussed.