Dielectric Properties of A, B-Site Mn-Doped LaTiO3+δ

Abstract

A-site Mn-doped La1-xMnxTiO3+δand B-site doped LaMnxTi1-xO3+δ(x = 0.1, 0.2) composites were synthesized by conventional solid-state reaction method. The low-frequency complex dielectric properties of the composites were investigated as functions of temperature (77 K ≤ T ≤ 360 K) and frequency (100 Hz ≤ f ≤ 1 MHz), respectively. The dielectric constants of A-site doped samples are higher than that of B-site doped samples. The loss tangents of the low doped samples are much less than that of the high doped samples. The A-site doped composites exhibit intrinsic dielectric response with a dielectric constant of ~40 in the temperature below 250 K. Interestingly, the dielectric constants of B-site doped composites always increased in the temperature range from 77 to 360 K. And it is clearly observed that extraordinarily low dielectric loss tangents appear in LaMn0.1Ti0.9O3+δ, which are much lower than that of LaMn0.2Ti0.8O3+δ. These changes indicate that the doped content can affect the intrinsic dielectric characteristics significantly.