In the present computational study,we found that Er∶Lu2O3 materials have promise for application in laser applications.The crystal structure and the electronic and optical properties of Er∶Lu2O3 materials were studied using first-principle calculations under the framework of density functional theory.Based on the experimental and calculated results,the structure of Lu2O3 was established.The calculated results show that doping by Er34 can effectively improve its absorption coefficient in the ultraviolet region and improve the static dielectric constant of Lu2O3.As the doping concentration of Er3+increases,the energy of the valence band electrons excited to the conduction band decreases,and the transition is more likely to occur.The absorption coefficient,reflectance,and electron energy loss spectroscopy are bathochromic shifted.The Lu2-xErxO3(0 ＜ x ≤ 0.09375)system still retains a low absorption coefficient reflectance in the mid-infrared and visible regions.Our calculations therefore show that rare earth Er3+doping can effectively regulate the electronic structure and optical properties of Lu2O3.