A novel approach of an infrared transparent Er:Y2O3–MgO nanocomposite for eye-safe laser ceramics

Abstract

Er³⁺ ion doped eye-safe lasers operating at a wavelength of 1.5 μm have attracted attention for use in many applications requiring protection from accidental retina exposure. For eye-safe lasers, it is considered important to improve the thermal and mechanical stability of the host materials for high power operation. Transparent Y₂O₃ is the most representative example among different types of host materials due to its low maximum phonon energy. However, this host shows low thermal conductivity with increasing dopant concentration. Herein, we prepare an Er:Y₂O₃–MgO nanocomposite as a new host material candidate that shows excellent optical, mechanical and thermal properties. By limiting domain coalescence and eliminating residual pores during sintering, outstanding optical transmittance is demonstrated for the Er:Y₂O₃–MgO nanocomposite. We also investigated the fluorescence spectrum and cross-section values to evaluate the possibility of using the Y₂O₃–MgO nanocomposite as a laser gain medium. The Er:Y₂O₃–MgO nanocomposite also shows excellent mechanical and thermal properties at high Er³⁺ ion dopant concentrations. The results indicate that Y₂O₃–MgO nanocomposite ceramics are promising candidate materials for use as high-power infrared laser hosts.