Investigation of electromagnetic properties of BiFeO3 by Time Differential Perturbed Angular Correlation (TDPAC) technique at ISOLDE

Time differential perturbed angular correlation (TDPAC) technique is one of the most sensitive techniques to study about the electric and magnetic fields at the individual lattice points. It benefits from the hyperfine interactions between the probe atom and its neighborhood. Multiferroic materials have been intensively studied to promote and understand the possibility of controlling magnetic properties by electric fields instead of magnetic fields which opens the path to faster, smaller, and more energy-efficient spintronic devices, such as memory elements, high-frequency magnetic devices, and micro-electro-mechanical systems, for data-storage technologies. BiFeO3 is one of the famous and important multiferroic materials since it shows both antiferromagnetic and ferroelectric behavior at room temperature. In this study, we report on the first time-differential perturbed angular correlation (TDPAC) measurements carried out on polycrystalline BiFeO3 samples using the nuclear probe 181Hf(181Ta) after implantation at the Bonn Radioisotope Separator (BONIS). The measurements have been done at a very broad temperature range from 296 K to 973 K and we have found the temperature dependent behaviors of the hyperfine interaction parameters and clearly observed the effects of the transition from anti-ferromagnetic to paramagnetic structure at Néel temperature. Two different lattice sites have been observed and these can be assigned to an undisturbed Fe-site and Fe-site with O vacancies in the lattice.