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The efficient preparation of inclined La 1-x Ca x MnO 3 (LCMO) films with excellent light-induced transverse thermoelectric (LITT) performance on c -axis miscut 12° SrTiO 3 single crystal substrates is achieved based on the home-designed metal-organic chemical vapor deposition (MOCVD) system. The LCMO films with the thickness of 300 nm are prepared in 1 min, and the preparation efficiency reaches 300 nm/min. Under the radiation of 248 nm pulsed laser with the duration time of 28 ns, the voltage signal of LCMO films shows high sensitivity of 3.13 V/mJ and fast response time of 28 ns, superior to the LITT performance of the reported LCMO under the irradiation of pulsed laser with similar wavelength and duration time. The improvement of LITT performance originates from good electrical conductivity and biaxial texture. Additionally, under the radiation of 900 nm continuous laser, the obvious response voltages can be detected in the LCMO films, and the voltage amplitudes increase linearly with increasing laser power densities. These results demonstrate the application potential of the light detectors composed of LCMO films based on the efficient preparation of MOCVD, and may provide a good prospect for developing low-cost and high-performance light detectors based on the LITT effect. • Efficient preparation of inclined La 1-x Ca x MnO 3 films is achieved based on MOCVD. • The inclined La 1-x Ca x MnO 3 films show outstanding LITT performance. • Good conductivity and biaxial texture are the keys to enhance LITT effect. [ABSTRACT FROM AUTHOR]

Abstract: Thin films of La1-xCaxMnO3 (, 0.51) have been deposited on LaAlO3 (LAO) and SrTiO3 (STO) substrates by magnetron sputtering (MS) and pulsed laser deposition (PLD). Lattice strain induced by substrate misfit results in drastic change of transport and magnetic properties. The very thin sample (thickness of ∼15nm) with deposited by MS on LAO substrate reveals compressive strained layer and semiconducting behaviour in zero magnetic field. Application of strong magnetic field of 7.5T leads to metallic behaviour and metal–insulator transition at a temperature about a bulk value of 250K. A sharp transition to a low-resistive state above a certain magnetic field is found at T<50K and associated with a significant hysteresis. Such a behaviour is similar to the phenomenon of melting of a charge ordered state by magnetic field that is first-order transition. Samples with substitution rate of deposited by PLD on LAO and STO substrates showed different behaviour due to variable strain of manganite layer. Magnetotransport properties of strained thin films are discussed due to the coexistence of ferromagnetic metallic and charge-ordered insulating phases and percolation processes. [Copyright &y& Elsevier]