Near white light and near-infrared luminescence in perovskite Ga:LaCrO<inf>3</inf>

We report the realization of near-white light emission (near-WLE) and the selective tuning to the near-infrared (NIR) luminescence from Ga substituted lanthanum chromite perovskite with electron-beam excitation for the first time. The near-WLE in Cathodoluminescence (CL), arises from the combination of 4T1(F)→4A2(blue), 4T1(P)→4A2(green) and 4T2→4A2(red) spin allowed transitions and 2E→4A2 spin forbidden transitions from the Cr3+ ion. The spin allowed transitions from the Cr3+ ions is rare, however can be accomplished by adjusting the Cr3+/Ga3+ ion concentration in the host lattice. The NIR emission originates from the selective 2E→4A2 transition, which increases with the increasing concentration of Ga3+ions. Moreover, the Density Functional Theory (DFT) calculations point out the presence of extra electronic states in the NIR region with Ga substitution, which elucidates the observation of NIR emission in Ga substituted samples.