Interstitial doping of Mn⁴⁺ ions: An effective method to optimize the optical properties of TeO₂ single crystal

AbstractTeO2 single crystal has drawn much attention in recent years due to its excellent acousto‐optic (AO) performance in the field of spectral imaging and optical processing. The optical properties of TeO2 single crystal are critical for the fabrication of AO devices. To improve the optical properties of the TeO2 single crystal, Mn4+ ions were doped into the TeO2 lattice. Herein, bulk TeO2 single crystal and TeO2:0.02Mn4+ single crystal have been successfully grown by a Bridgman method. Compared with the TeO2 single crystal, a 30% transmittance increase was observed in the TeO2:0.02Mn4+ single crystal. Furthermore, the TeO2:0.02Mn4+ single crystal shows a smaller extinction coefficient (≤0.01) in the Vis–NIR region, indicating less optical loss. The bandgap energy of TeO2:0.02Mn4+ was broadened from 3.360 to 3.635 eV. In addition, TeO2:0.02Mn4+ single crystal exhibits a higher refractive index (about 2.244), which indicates that TeO2:0.02Mn4+ single crystal is a potential medium for high‐efficiency AO devices.