Influence of A-site Tb3+ doping on the microstructure, optical and magnetoelectric properties of ErCrO3

In this paper, Er_1-xTb_xCrO₃ (0 ≤ x ≤ 0.5) samples were prepared by solid phase method. The effects of A-site Tb³⁺ doping on the microstructure, optical and magnetoelectric properties of ErCrO₃ were investigated systematically. The XRD patterns of all samples are consistent with the orthogonal distorted perovskite structure and belong to the Pbnm space group. Tb³⁺ ions increased the lattice constant of ErCrO₃ sample and reduced lattice distortion and optical band gap. It also leads to a decrease in the concentration of vacancy defects in the parent compound. The anomalous increase of lattice constants at x = 0.1 is related to the creation of vacancy defects, and is confirmed by positron annihilation lifetime spectra and FTIR spectroscopy. The antiferromagnetic transition temperature T_N(Cr) and the coercivity field H_c gradually increase with Tb³⁺ ions, and the peak decrease near T_SR, while an exchange bias effect is produced. Dielectric measurements indicate that Tb³⁺ ions effect the Er–Er and Er–Cr interactions, and the dielectric constants of the sample change with the of Tb³⁺ doping amount.