Antiferroelectric order and Ta-doped AgNbO3 with higher energy storage density

Abstract

Antiferroelectric phenomenological theory can well depict the behavior of the antiferroelectric system, but how to quantitatively define the antiferroelectric order parameter based on the experimental results is still an open question. In this work, the reduced antiferroelectric order parameter is proposed based on the direct atomic-scale observation, which can be regarded as an extension of the traditional antiferroelectric order parameter. In addition, the enhancement of energy storage density of Ta-doped silver niobate is discussed using this reduced antiferroelectric order parameter as a tool. It is found that the deeper reason for the increase of energy storage density can be attributed to the decrease of the permittivity χ 0 of the corresponding paraelectric phase, and novel antiferroelectric materials with high energy storage density may be realized on the base of it.