Spectroscopic characterization of photoinducedMn5+ions inYAlO3

Abstract

We have spectroscopically studied the photoinduced color center in ${\mathrm{M}\mathrm{n}:\mathrm{Y}\mathrm{A}\mathrm{l}\mathrm{O}}_3,$ the promising material for holographic data storage. We have proved that grayish-bluish coloration in photoexposed ${\mathrm{M}\mathrm{n}:\mathrm{Y}\mathrm{A}\mathrm{l}\mathrm{O}}_3$ is due to ${\mathrm{Mn}}^{5+}$ ions in octahedral sites. We assign the main features observed in the absorption and emission spectra of photodarkened ${\mathrm{M}\mathrm{n}:\mathrm{Y}\mathrm{A}\mathrm{l}\mathrm{O}}_3$ to the ${}^1{T}_2{(t}_2^2),$ ${}^3{T}_2{(t}_{2}e),$ ${}^3{T}_1{(t}_{2}e),$ ${}^1{A}_1{(t}_2^2),$ and ${}^3{A}_2{(e}^2)$ excited states of ${\mathrm{Mn}}^{5+}.$ We show that ${\mathrm{Mn}}^{5+}$ ions can be stabilized in ${\mathrm{M}\mathrm{n}:\mathrm{Y}\mathrm{A}\mathrm{l}\mathrm{O}}_3$ codoped with Ca ions and in the crystals grown in reducing atmosphere and subsequently annealed in air at 310–460 °C.