The Observation of Ferroelastic and Ferrielectric Domains in AgNbO3 Single Crystal

TL;DR

This study reports the discovery of coexisting ferroelastic and ferrielectric domains in AgNbO3 single crystals, revealing a polar ferrielectric ground state at room temperature, which clarifies previous controversies.

Contribution

It provides the first direct observation of ferroelastic and ferrielectric domains in AgNbO3 single crystals, offering new insights into its ground state and electromechanical properties.

Findings

Coexistence of ferroelastic and ferrielectric domains observed

AgNbO3 single crystal is in a polar ferrielectric phase at room temperature

Weak electromechanical response from the ferrielectric phase

Abstract

Compared to AgNbO3 based ceramics, the experimental investigations on the single crystalline AgNbO3, especially the ground state and ferroic domain structures, are not on the same level. Here in this work, based on successfully synthesized AgNbO3 single crystal using flux method, we observed the coexistence of ferroelastic and ferrielectric domain structures by a combination study of polarized light microscopy and piezoresponse force microscope, this finding may provide a new aspect for studying AgNbO3. The result also suggests a weak electromechanical response from the ferrielectric phase of AgNbO3 which is also supported by the transmission electron microscope characterization. Our results reveal that the AgNbO3 single crystal is in a polar ferrielectric phase at room temperature, clarifying its ground state which is controversial from the AgNbO3 ceramic materials.