- Letter
Room-temperature persistent photoconductivity of
Phys. Rev. Materials 8, L111601 – Published 13 November, 2024
DOI: https://doi.org/10.1103/PhysRevMaterials.8.L111601
Abstract
Potassium tantalate () single crystals annealed in hydrogen exhibit room-temperature persistent photoconductivity. The oxygen-poor annealing environment creates oxygen vacancies that are substituted with hydrogen. A photon of energy near the indirect bandgap (3.65 eV) can excite this defect, resulting in free electrons in the conduction band. This causes an increase in n-type conductivity of 4 orders of magnitude with a recovery time of 2–4 years. Hydrogen leaves the O site and forms an O–H bond that is observed by IR spectroscopy. The microscopic origin of the defect model is corroborated by hybrid density functional theory calculations.
Physics Subject Headings (PhySH)
Corrections
24 September, 2025
Correction: Incorrect versions of Figures 2(a), 2(b) and Figure 3 were used for publication and have now been replaced with the correct versions. A value in the sixth sentence of the eighth paragraph and fourth sentence of the penultimate paragraph was incorrect and has been fixed.
