Lovro Fulanovic^1,*, Mao-Hua Zhang¹, Binxiang Huang¹, Nikola Novak² and  Jurij Koruza<sup>1,3

1</sup> Department of Materials and Earth Sciences, Technical University of Darmstadt, Germany.
² Department of Condensed Matter Physics, Jozef Stefan Institute, Ljubljana, Slovenia.
³ Institute for Chemistry and Technology of Materials, Graz University of Technology, Austria.
^* Presenting author: fulanovic@ceramics.tu-darmstadt.de

Antiferroelectrics (AFEs) feature unique properties due to their electric field-induced phase transition to the ferroelectric (FE) phase. AFE are namely characterized by high values of dielectric permittivity which is both temperature and electric field dependent. In contrast to the other dielectric materials, AFE exhibit a sharp increase of permittivity with increasing electric field when approaching the AFE/FE phase transition [1]. It was suggested that the electric field induced phase transition is responsible for the peculiar dielectric behavior of antiferroelectrics. However, some of lead-free AFE do not exhibit such a dielectric behavior, although they exhibit double loop of polarization versus electric field. Hence, the mechanisms contributing to the peculiar dielectric behavior are still not understood. Even more, the dielectric behavior of antiferroelectrics is an important feature for realizing high voltage DC-link or snubber capacitors needed in emerging green technologies.
In order to elucidated field dependent permittivity in AFE lead-free AFE NaNbO₃ and AgNbO₃ are contrasted to the PbZrO₃-based composition [2,3], with a focus on AFE/FE phase transition. Series of comprehensive permittivity measurement were performed, under different AC and DC fields, and in a broad temperature range. In addition, phase transition properties were complemented with polarization versus field data. The results were compiled in the electric field vs temperature diagrams, a figure of merit for the field induced phase transitions.    

References
[1] B. Jaffe, Proc. IRE. 49, 1961.
[2] M.-H. Zhang et al., Acta Mater., 2020, 200, 127-135.
[3] L. Fulanovic et al., J. Eur. Ceram. Soc., 2021, 41, 5519-5525.