Convenient method for Curie temperature determination in holmium and yttrium manganite based on capacitance value

Abstract

This study reported an alternative technique to measure the Curie temperature (Tc) of hexagonal manganite as multiferroic sample. The method is based on change identification in slope of capacitance value as a function of temperature. Temperature variation of the capacitance observed in holmium and yttrium manganite sintered at 1250 °C has been studied respectively. The optimum preparation of holmium and yttrium manganite with space group P63cm by using high energy ball milling has been chosen in order to provide a convenient Tc. The changes of the capacitance value as a function of temperature range from 300 up to 1000 K at 50 Hz has been carried out in order to obtained the Tc value. Results obtained from the experiments showed that Tc transition could be clearly exhibited by the capacitance value for both the holmium manganite and yttrium manganite samples. The measured property values gave their Tc transition around reported value in previous studies. The ferroelectric Tc transition was observed to be 850 K and 860 K for HoMnO3 and YMnO3 respectively. A completely intrinsic behaviour of Tc was revealed by our simple and low cost method since no applied external field was used, yielding a truly spontaneous ferroelectric behaviour.