Enhanced magnetic, dielectric and ferroelectric properties of La_0.9Er_0.1FeO₃

Samples of LaFeO₃ and Er³⁺ doped therein (La_0.9Er_0.1FeO₃) are prepared by modified sol-gel method. Investigations of magnetic, dielectric and ferroelectric properties of La_0.9Er_0.1FeO₃ (LEFO) are carried out. X-ray diffraction pattern of each of the sample is analyzed using Rietveld analysis which confirms the pure crystallographic phase formation of all the samples and reveals that a compressive lattice distortion is introduced due to Er³⁺ doping. Magnetic hysteresis loops of LFO and LEFO recorded at 300 and 5 K which exhibit that the value of maximum magnetization of the doped sample is enhanced compared to that of the pristine sample and the thermal variation of magnetization of LEFO under zero field cooled and field cooled conditions suggests an antiferromagnetic to ferromagnetic phase transition below ~70 K. Dielectric properties of LFO and LEFO are investigated in the frequency range from 42 KHz - 5 MHz at different temperatures from 300 to 850 K which exhibits that the value of loss tangent (tanδ) decreases compared to that of LFO. Thermal variation of exhibits a ferroelectric to paraelectric phase transition at ~720 K. Polarizations vs. electric field (P-E) loops of LEFO are recorded at 300 K which are also enhanced compared to that of bare LFO. This enhanced magnetic property together with the electrical properties will improve its quality for application in electronic devices. (author)