Near infrared luminescence of CuLa1 − xLnxO2 (Ln: lanthanide ions) due to 4f transitions of Ln3+ in the site with inversion symmetry

► CuLa0.98Ln0.02O2 with Ln3+ = Nd3+, Pr3+ showed photoluminescence around 1200 nm. ► Near-infrared luminescence of CuLa0.98Ln0.02O2 could be assigned as 4f transitions. ► Some Ln3+ at site with inversion symmetry show unique luminescence.