Specific Heat and the Dielectric Properties of Bi 0.8 Ho 0.2 FeO 3 Multiferroic

The specific heat and the dielectric permittivity of Bi0.8Ho0.2FeO3 multiferroics have been studied in the wide temperature range 300–750 K. The doping with rare-earth element holmium is found to lead to substantial changes in the temperature dependences of specific heat Cp and dielectric permittivity e' at high temperatures. The additional contribution to the specific heat is shown can be interpreted as a Schottky anomaly for three-level states which form due to a distortion of the lattice parameters as a result of doping. Additional anomaly characteristic of a phase transition is observed in temperature dependences of Cp and e'. The results are discussed in combination with the data of structural studies.