Birefringence induced by antiferroelectric switching in transparent polycrystalline $PbZr_{0.95}Ti_{0.05}O_{3}$ film

TL;DR

This study demonstrates how electric field-induced phase transitions in a transparent polycrystalline antiferroelectric film cause measurable birefringence changes, revealing insights into switching dynamics and irreversibilities.

Contribution

It provides the first direct observation of birefringence changes due to antiferroelectric switching in a transparent polycrystalline film using simple transmission measurements.

Findings

Field-induced birefringence is observable despite polycrystalline nature.

Birefringence exhibits both rapid and slow dynamics.

Long saturation times suggest complex relaxation processes.

Abstract

The most characteristic functional property of antiferroelectric materials is the possibility to induce a phase transition from a non-polar to a polar phase by an electric field. Here, we investigate the effect of this field-induced phase transition on the birefringence change of $PbZr_{0.95}Ti_{0.05}O_{3}$. We use a transparent polycrystalline $PbZr_{0.95}Ti_{0.05}O_{3}$ film grown on $PbTiO_{3}/HfO_{2}/SiO_{2}$ with interdigitated electrodes to directly investigate changes in birefringence in a simple transmission geometry. In spite of the polycrystalline nature of the film and its moderate thickness, the field-induced transition produces a sizeable effect observable under a polarized microscope. The film in its polar phase is found to behave like a homogeneous birefringent medium. The time evolution of this field-induced birefringence provides information about irreversibilities in the antiferroelectric switching process and its slow dynamics. The change in birefringence has two main contributions, one that responds briskly (~ 0.5 s), and a slower one that rises and saturates over a period of as long as 30 minutes. Possible origins for this long saturation and relaxation times are discussed.