Absorption Spectrum of Optically Pumped Ruby I. Experimental Studies of Spectrum in Excited States

Abstract

Absorption transitions between two excited optical states in ruby have been studied by comparing the absorption coefficients measured under optically pumped and unpumped conditions. The spectrum has been determined in the π-and σ-polarizations in the photon energy range from 5,500 to 45,000 cm -1 . Several absorption bands have been found which arise from the transitions from the excited states t 2g 3 2 E g and t 2g 3 2 T 1g of the Cr 3+ ion. From the locations and intensities of these bands, the terminal states of the observed transitions are assigned to the charge transfer state, the t 2g 3 2 T 2g state, and the doublet states belonging to the electron configuration t 2g 3 e g . Calculated energies between these states and the metastable states, t 2g 3 2 E g and t 2g 3 2 T 1g , are in good agreement with the peak energies of the observed absorption bands. The present experiment gives new information inaccessible by the ordinary ground state absorption measurement, such as the locations of several double...