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Gd1Ba2Cu3O7–δ/SrTiO3 (Gd123/STO) superconductor film (~ 200 nm) was prepared using pulsed laser deposition technique. X-ray diffraction pattern of film reveals the polycrystalline growth with the lattice mismatch ~ 0.25% between the film and substrate. From the resistive behavior, it is clear that Gd123 film exhibits TConset ~ 89 K and TCR = 0 ~ 78 K while mean field TC is ~ 83 K. Temperature dependent resistivity (2–150 K) studies in various applied magnetic fields have been understood on the basis of thermally activated flux flow mechanism. It is observed that the pinning energy decreases with increase in applied magnetic field. To understand the transport mechanism and field effect of magnetic field on the conduction in normal state of film, all the resistivity plots were fitted, where power law is found to increase with increase in applied magnetic field which indicates the field induced enhancement in the inter-band charge carrier scattering in Gd123 film. [ABSTRACT FROM AUTHOR]

BiFeO3 thin films were deposited onto single crystalline Si (100) substrate using Pulsed Laser Deposition technique. The effect of different oxygen partial pressure on the BiFeO3 film growth, structural and transport properties has been investigated. Structural characterization shows that film growth under lower partial pressure exhibits a minor impurity phase which gets suppressed under higher oxygen partial pressure (OP2). The effect of OP2 during the deposition on the leakage current and the role of oxygen vacancies have been understood in the context of various charge transport mechanism. RBS study confirms the presence of oxygen content in the film studied which are responsible for the modification in the Electrical behavior of BFO/Si thin film devices. [ABSTRACT FROM AUTHOR]

In this communication, we report results of the electrical transport properties across the interface of composites consisting of n-type LaMnO3−δ (LMO) and p-type La0.7Ca0.3MnO3 (LCMO) manganites grown on LaAlO3 (LAO) single crystalline substrates using low cost wet chemical solution deposition (CSD) and sophisticated, well-controlled dry chemical vapor deposition (CVD) chemical techniques. The XRD Φ-scan studies reveal the single crystalline nature of both bilayered composites, with parallel epitaxial growth of LMO and LCMO layers onto the LAO substrate. The valence states of Mn ions in both layers of both composites were identified by performing X-ray photoelectron spectroscopy (XPS). The I–V characteristics of the LMO/LCMO interfaces show strong backward diode-like behavior at higher applied voltages well above the crossover voltage (VNB). Below VNB, the interfaces demonstrate normal diode-like characteristics throughout the studied temperature range. The electric field-induced modulation of the LMO/LCMO junction resistance of the interfaces has been observed. Electric field-dependent electroresistance (ER) modifications at different temperatures have also been studied. The electrical transport properties have been discussed in the context of various mechanisms, such as charge injection, tunneling, depletion region modification and thermal processes across the interface. The effects of structurally and chemically developed sharp interfaces between the LMO and LCMO layers on the transport properties of the presently studied bilayered thin film composites have been discussed on the basis of correlation between the physicochemical characterization and charge transport behavior. A comparison of different aspects of the transport properties has been presented in the context of the structural strain and crystallinity of the composites grown using both wet and dry chemical techniques. [ABSTRACT FROM AUTHOR]

In this communication, structural, microstructural, transport and magnetotransport properties are reported for La0.7Pb0.3MnO3/LaAlO3 (LPMO/LAO) manganite films having different thicknesses. All the films were irradiated with 200 MeV Ag+15 swift heavy ions (SHI). Films were grown using the sol–gel method by employing the acetate precursor route. Structural measurements were carried out using the X-ray diffraction (XRD) method at room temperature, while atomic force microscopy (AFM) was performed for the surface morphology. Temperature dependent resistivity under different applied magnetic fields for all the films shows metal to insulator transition at temperature TP. In addition to the metal to insulator transition at TP, the films also exhibit low temperature resistivity upturn behavior. Resistivity, TP and upturn behavior are highly influenced by the film thickness, applied magnetic field and irradiation. To understand the nature of charge transport for the low temperature resistivity behavior and metallic and insulating (semiconducting) regions, various models and mechanisms have been verified and the most suitable mechanism has been found for each region in the resistivity curves. Magnetoresistance (MR) is affected by temperature, film thickness and irradiation. MR behavior has been understood in terms of combined and separate contributions from grains and grain boundaries in the films. [ABSTRACT FROM AUTHOR]

In this communication, we report results of the electrical transport properties across the interface of composites consisting of n-type LaMnO 3-δ (LMO) and p-type La 0.7 Ca 0.3 MnO 3 (LCMO) manganites grown on LaAlO 3 (LAO) single crystalline substrates using low cost wet chemical solution deposition (CSD) and sophisticated, well-controlled dry chemical vapor deposition (CVD) chemical techniques. The XRD ϕ-scan studies reveal the single crystalline nature of both bilayered composites, with parallel epitaxial growth of LMO and LCMO layers onto the LAO substrate. The valence states of Mn ions in both layers of both composites were identified by performing X-ray photoelectron spectroscopy (XPS). The I-V characteristics of the LMO/LCMO interfaces show strong backward diode-like behavior at higher applied voltages well above the crossover voltage (V NB ). Below V NB , the interfaces demonstrate normal diode-like characteristics throughout the studied temperature range. The electric field-induced modulation of the LMO/LCMO junction resistance of the interfaces has been observed. Electric field-dependent electroresistance (ER) modifications at different temperatures have also been studied. The electrical transport properties have been discussed in the context of various mechanisms, such as charge injection, tunneling, depletion region modification and thermal processes across the interface. The effects of structurally and chemically developed sharp interfaces between the LMO and LCMO layers on the transport properties of the presently studied bilayered thin film composites have been discussed on the basis of correlation between the physicochemical characterization and charge transport behavior. A comparison of different aspects of the transport properties has been presented in the context of the structural strain and crystallinity of the composites grown using both wet and dry chemical techniques.

Correction for 'Charge transport mechanisms in sol-gel grown La 0.7 Pb 0.3 MnO 3 /LaAlO 3 manganite films' by Eesh Vaghela et al., Phys. Chem. Chem. Phys., 2017, DOI: 10.1039/c6cp07730g.

In this communication, structural, microstructural, transport and magnetotransport properties are reported for La 0.7 Pb 0.3 MnO 3 /LaAlO 3 (LPMO/LAO) manganite films having different thicknesses. All the films were irradiated with 200 MeV Ag +15 swift heavy ions (SHI). Films were grown using the sol-gel method by employing the acetate precursor route. Structural measurements were carried out using the X-ray diffraction (XRD) method at room temperature, while atomic force microscopy (AFM) was performed for the surface morphology. Temperature dependent resistivity under different applied magnetic fields for all the films shows metal to insulator transition at temperature T P . In addition to the metal to insulator transition at T P , the films also exhibit low temperature resistivity upturn behavior. Resistivity, T P and upturn behavior are highly influenced by the film thickness, applied magnetic field and irradiation. To understand the nature of charge transport for the low temperature resistivity behavior and metallic and insulating (semiconducting) regions, various models and mechanisms have been verified and the most suitable mechanism has been found for each region in the resistivity curves. Magnetoresistance (MR) is affected by temperature, film thickness and irradiation. MR behavior has been understood in terms of combined and separate contributions from grains and grain boundaries in the films.