Low temperature superlattice in monoclinic PZT

TL;DR

This paper investigates the low-temperature phase behavior of Pb(Zr0.52Ti0.48)O3, revealing a monoclinic phase and a nanoscale distorted variant, clarifying the origin of superlattice peaks and supporting theories of coexisting ferroelectric and rotational instabilities.

Contribution

It provides experimental evidence of a superlattice phase in monoclinic PZT and clarifies the origin of superlattice peaks, supporting theoretical predictions.

Findings

Identification of a monoclinic phase at low temperatures.

Discovery of a nanoscale distorted phase due to oxygen octahedra rotation.

Clarification of superlattice peak origins in PZT.

Abstract

TEM has shown that the strongly piezoelectric material Pb(Zr0.52Ti0.48)O3 separates into two phases at low temperatures. The majority phase is the monoclinic phase previously found by x-ray diffraction. The minority phase, with a nanoscale coherence length, is a slightly distorted variant of the first resulting from the anti-phase rotation of the oxygen octahedra about [111]. This work clears up a recent controversy about the origin of superlattice peaks in these materials, and supports recent theoretical results predicting the coexistence of ferroelectric and rotational instabilities.