Influence of the stoichiometry in the site distribution of Cr3+ ions in LiNbO3

Abstract

In this letter the influence of the stoichiometry ([Li]/[Nb] ratio) on the R absorption lines of Cr3+ in LiNbO3 has been investigated. It is shown that Cr3+ ions occupy the Li+ and Nb5+ lattice sites but their relative distribution is modified by changing the melt composition ([Li]/[Nb] ratio). It has been also concluded that the defects associated to the nonstoichiometry (antisites and Nb vacancies) of the crystal host are responsible for the incorporation of Cr3+ ions into the LiNbO3 matrix.