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We report the results of temperature dependent magnetotransport measurements on PLD grown GdBa2Cu3OZ (Gd-123) film in the superconducting transition region, TC0 < T < TConset. It is observed that, on application of magnetic field (0 – 14T), TConset (temperature at which superconducting transition starts) remains unchanged while TC0 (temperature at which resistance becomes zero) gets suppressed with field, resulting in the increase in superconducting transition width (ΔTC). Effect of applied field on the flux dynamics, in superconducting transition region, has been understood in the light of thermally activated flux flow (TAFF) model and variation in pinning energy (U0) in Gd-123.

Nanostructured Y0.95Ca0.05MnO3 (YCMO) samples have been synthesized using cost effective sol-gel method. The samples were sintered at various temperatures ranging between 700 – 1100°C (ST). XRD studies reveal the single phasic nature of the samples. Frequency dependent dielectric (e) and modulus (M) behaviors of YCMO samples imply the increase in e and activation energy (Ea) with ST which has been discussed in the light of oxygen vacancies and grain morphology.

We report the effect of Cu-doping on the dielectric behavior of NdMn1−xCuxO3 (NMCO); x = 0.0 – 0.05, manganites. It is observed that, dielectric constant (e′) decreases with Cu (x) concentration which has been understood on the basis of modifications in grain morphology and double exchange (DE) interaction between Mn3+ and Mn4+. Also, effect of grain boundary (GB) density on the dielectric response is studied using cole-cole plots.

In this study, we report the results of the electrical property measurements on Ca2+− doped Y0.95Ca0.05MnO3 (YCM) manganite thin film grown on n-type Si- substrate, using chemical solution deposition (CSD) technique. I-V characteristics show that, film exhibits rectifying behavior with high electroresistance(ER) which decreases with temperature. It is shown that, charge transport follows space charge limited current (SCLC) mechanism.

Effect of semiconductor channel carrier concentration on the modifications in the electrical properties of Ag/BaTiO3/SrTiO3/ZnO Metal-Ferroelectric-Insulator-Semiconductor (MFIS) heterostructure has been investigated. Under 4 V applied voltage, low leakage current density ∼3.2 × 10−6 A/cm2, has been observed in ZnO based MFIS heterostructure, which becomes ∼5.0 × 10−6 A/cm2 for MFIS with Al:ZnO channel. Observation of counterclockwise butterfly shaped C-V behavior confirms that, hysteresis in C-V is due to spontaneous ferroelectric polarization and field effect. A device with ZnO semiconductor exhibit ∼2700% modulation which decreases to ∼800% for Al: ZnO channel with good retention behavior. Pulse induced write/erase repeatability of source/drain current confirms the usefulness of the presently studied devices for non-volatile switching memory application.