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Charge transport studies on pulsed laser deposition grown Y0.95Ca0.05MnO3 (YCMO) thin film on (100) single crystalline Nb:SrTiO3 (SNTO) substrate. X-ray diffraction analysis reveals the single phase nature of YCMO manganite film having lattice mismatch between YCMO thin layer and SNTO substrate. Surface morphology, studied using atomic force microscopy, indicates the presence of island like grain growth with narrow size distribution. Transport properties have been studied by performing temperature dependent resistivity under different applied voltages across the YCMO/SNTO interface to understand the charge conduction across the same interface. The observed electric field-induced modifications in interface resistance across the YCMO/SNTO lattice have been discussed in the contexts of barrier between YCMO and SNTO, oxygen vacancies, structural disorder and structurally strained region at the film–substrate interface. Electrical resistance has been theoretically fitted using various models and mechanisms to better understand the charge conduction mechanisms in the semiconducting region for the YCMO/SNTO interface. [ABSTRACT FROM AUTHOR]

In this study, we investigate the effect of ion irradiation on Y0.95Ca0.05MnO3 (YCMO) thin films. X-ray diffraction and Raman spectroscopy measurements show single-phase and strain/stress modifications with ion irradiation. Rutherford backscattering spectrometry confirms the variation in oxygen vacancies. The near-edge x-ray absorption fine structure shows valence state reduction of Mn ions, which is attributed to oxygen vacancies. The optimal resistive switching ratio is observed at the lowest fluence (1 × 1011 ions/cm2) of ion irradiation. At higher fluences (1 × 1012 and 1 × 1013 ions/cm2), the strain relaxation and oxygen vacancy annihilation are ascribed to the local annealing effect. The double logarithmic curve and modified Langmuir–Child's law satisfy the space charge limited conduction mechanism in all thin films. These results suggest the crucial role of irradiation-induced oxygen vacancies in modifying the electronic structure and electrical properties of YCMO thin films. [ABSTRACT FROM AUTHOR]

In this communication, structural, microstructural and low magnetic field influenced dielectric and impedance have been investigated for low cost chemically grown Bi 0·85 La 0·15 FeO 3 thin film grown on FTO glass substrate by using sol–gel spin coating method. X–ray diffraction (XRD) reveals the successful growth of Bi 0·85 La 0·15 FeO 3 film on FTO substrate. Surface morphology of the film has been examined by scanning probe method. Magnetoelectric (ME) properties of the film have been understood at room temperature. Magnetic field influenced dielectric behavior has been systematically investigated in the frequency range of 20 Hz to 2 MHz. The magnetic field induced alterations in the dielectric constant and impedance behavior at different frequencies confirm the complex nature of ME coupling between spin and lattice of BLFO film. Magnetic field dependent conductivity behaviors show a complex governance of charge carrier movements by the lattice disorder effect and spin alignment of iron ions in the BLFO lattice. • Chemical growth of Bi 0·85 La 0·15 FeO 3 thin layer on FTO substrate. • Interesting dielectric and impedance behaviors. • Appealing magnetodielectric and magnetoimpedance characters of multiferroic. [ABSTRACT FROM AUTHOR]

Herein, the bipolar resistive switching of Y0.95Sr0.05MnO3 (YSMO) film grown on a Si substrate by pulsed laser deposition is reported. The mixed valent state of Mn ions with the presence of oxygen vacancies is confirmed by near‐edge X–ray absorption fine structure. The temperature‐dependent mobility and other switching parameters are extracted using Murgatroyd expression and a space charge–limited mechanism in the high‐resistance state. The YSMO thin film shows better resistive switching as the switching layer (a layer close to a positively biased electrode) thickness decreases. The bipolar resistive switching of the film suggests a strong dependence on localized switching thickness and temperature. [ABSTRACT FROM AUTHOR]

Herein, an enhancement in the resistive switching of Y0.95Sr0.05MnO3 (YSMO) films by swift heavy ion (SHI) irradiation‐induced electronic excitations is shown. YSMO films are prepared by pulsed laser deposition on a single‐crystalline Si substrate. For electronic excitations, Ag15+ ions with 200 MeV energy are used with ion fluences of 1 × 1011 (YS1), 1 × 1012 (YS2), and 1 × 1013 (YS3) ions per cm2. X‐ray diffraction shows increase in tensile strain up to YS2 film followed by strain relaxation in YS3 film. Red shifting of Raman active modes signifies the phonon softening due to tensile strain in pristine (YSP) to YS2 films. Atomic force micrographs show that the number and size of defects are increased, indicating the irradiation‐induced defect formation, which is suppressed for the YS3 film. Rutherford backscattering spectrometry demonstrates decreased oxygen peak intensities for YS1 and YS2 films, denoting increased oxygen vacancies. Near‐edge X‐ray absorption fine structure displays a reduction in Mn valence state from Mn4+ to Mn3+, signifying the formation of oxygen vacancies for films up to YS2. The enhancement of resistive switching is governed by tuning the SHI‐induced oxygen vacancies. The present study demonstrates that YSMO films are suitable as emerging candidates in memory device applications. [ABSTRACT FROM AUTHOR]

In the present communication, for understanding the properties of thickness dependent STO/ITO thin films, the films were prepared using sol–gel sputtering technique wherein, different STO thickness are grown over ITO substrate. The structural properties understood using the XRD patterns wherein, observation shows the presence of amorphous STO without any detectable impurities. The Microstructural and cross-section analysis gives insight information of the films with batter distribution of grain and upper portion (STO) and lower portion (ITO) respectively which gets modifies with different thicknesses. The elemental composition of the studied films observed using EDAX and XPS spectrum reveals the only presence of required material with homogeneous distribution of all elements. From the a.c. conductivity and impedance spectroscopy the electrical properties of the films were measured wherein, for understanding the insight information's the theoretical model such as; Jonscher's power law, and Nyquist plot were fitted. The alternation of the properties can be studied using grain, grain boundaries, thickness of the film and different derived parameters. [ABSTRACT FROM AUTHOR]

Multiferroic thin films of BiFe 0.98 Co 0.02 O 3 (BFCO) were grown on Al 2 O 3 (ALO) substrates having a buffer layer of Al (2%) doped ZnO (ZAO) prepared by using chemical solution deposition (CSD) method. Effect of annealing temperature and annealing atmosphere on the structural, microstructural, dielectric, leakage, transport, magnetic and magnetodielectric (MD) properties of films have been investigated. BFCO/ZAO/ALO films grown under oxygen atmosphere show better crystallinity, smooth surface and slightly larger grain size than that of the films annealed in air. Lower leakage current, higher dielectric constant, lower dielectric loss, lower a.c. conductivity and larger MD and magnetoimpedance (MI) effects have been observed for the film annealed at 550 °C under oxygen atmosphere. In order to verify the state of oxygen vacancies, photoluminescence spectra have been studied. Room temperature magnetic behavior of the BFCO/ZAO/ALO films has been studied by performing magnetization measurements. The effect of magnetic field on the dielectric constant and impedance (MD & MI) have been discussed on the basis of magnetostriction effect and mobility of interfacial charges at grain boundaries and bilayer interface. Image 1 • CSD grown BiFe 0.98 Co 0.02 O 3 thin films with a buffer layer of Al doped ZnO fabricated on Al 2 O 3 substrates. • Oxygen vacancy related transport properties. • Effect of annealing conditions on microstructure, dielectric, and magnetodielectric properties. • Magnetic field effect on mobility of interfacial charges at grain boundaries and bilayer interface. [ABSTRACT FROM AUTHOR]