Electrical properties of Yttrium(Y) doped LaTiO3

Abstract

The perovskite structure has shown enormous utility in many facets of science in the past 50 years. From applications in high-temperature superconductors to piezoelectric sensors, the perovskite structure has been used in a wide array of cutting-edge areas of solid-state physics and materials science. LaTiO3 has a perovskite type crystal structure. It undergoes three phase transitions. At 50-100 K LaTiO3 undergoes a magnetic phase transition. John –Teller phase transition occurs between 100 K and 300 K. Also, insulator-metal (I-M) transition occurred at 500-550k. On the other hand, YtiO3 also have perovskite type crystal structure. It undergoes I-M phase transition around 750 K. We are interested to know the effect of the electrical and dielectric properties by replacing La with Y (Yttrium). To investigate the electrical and dielectric properties of La1-xYxTiO3 [x = 0.0, 0.2, 0.3 0.4 and 0.6] system, samples have been prepared by solid state reaction method. To confirm the crystal structure, room temperature X-ray diffractions were performed and no extra pack was observed. The measurement of frequency dependence dielectric constant shows that the decreases in dielectric constant observed with increase in frequency and the value of dielectric constant increase with increasing concentration of Y (Yttrium). We also observed that loss tangent decrease with increasing frequency and increase in concentration of Y (Yttrium) results to decrease in the value of loss tangent. The cole-cole plot shows that the grain size decrease with increasing concentration of Y (Yttrium), as a result resistivity decrease while conductivity increases with increasing concentration of Y (Yttrium).