Light-induced transverse thermoelectric effect in MOCVD-deposited La_1−xSr_xMnO₃ (0.08 ≤ x ≤ 0.7) thin films with inclined structure

Usually, modulating electrical transport properties is a vital means to improve the light-induced transverse thermoelectric (LITT) effect. The manganese perovskite-type oxides La_1−xA_xMnO₃ (A = Ca, Sr, etc.) are typical materials with the LITT effect. However, much attention is paid to La_1−xCa_xMnO₃, and few studies focus on low-resistivity La_1−xSr_xMnO₃. In this work, the La_1−xSr_xMnO₃ (0.08 ≤ Sr ≤ 0.7) thin films with inclined structures are prepared based on the metal-organic chemical vapor deposition (MOVCD) method. The XRD and TEM results indicate that La_1−xSr_xMnO₃ (0.08 ≤ Sr ≤ 0.7) thin films feature high c-axis orientation and good biaxial textures. Adjusting Sr content modulates the electrical transport properties of the thin films, the response voltage is significantly improved. Especially, the lowest resistivity of 0.2 × 10⁻² Ω·cm is achieved in La_0.7Sr_0.3MnO₃ thin film, thus achieving a fast response time of 24 ns upon the irradiation of a 248 nm pulse laser, significantly lower than most literature results for La_1−xCa_xMnO₃. This work demonstrates the potential of La_1−xSr_xMnO₃ in ultraviolet pulse laser detectors.