Thermal, magnetic and electrical properties of Tb 1−x Dy x MnO 3 multiferroics

Abstract A series of multiferroic materials with the compositional formula, Tb 1− x Dy x MnO 3 (where x =0, 0.1, 0.2, 0.3 and 0.4) were prepared by the sol gel method. After characterizing the samples structurally, a systematic investigation of specific heat, magnetization and dielectric properties over the temperature range, 4–300 K, was undertaken. Based on these studies, it was found that all the samples exhibit a transition at 40 K and the observed behavior may be attributed to the ordering of Mn 3+ ions. Further, all the five samples are found to exhibit a ferroelectric transition in the temperature range 20–24 K. Finally, yet another transition was also exhibited by all the samples at temperatures below 10 K and is attributed to the antiferromagnetic (AF) ordering of rare-earth ionic moments. The magnetic entropy of all the samples was also computed with the help of their heat capacity data.