High piezoelectric coefficient of single domain Mn-doped NBT-6%BT single crystals

TL;DR

This study demonstrates that Mn-doped NBT-6%BT single crystals can achieve exceptionally high piezoelectric coefficients of up to 570 pC/N when properly poled, with domain structures influencing their piezoelectric performance.

Contribution

The paper reports the stabilization of single domain states in Mn-doped NBT-6%BT crystals and achieves record-high piezoelectric coefficients through domain engineering.

Findings

Single domain states can be stabilized by poling along [001].

Piezoelectric coefficient d33 reaches 570 pC/N in optimized crystals.

Multidomain crystals show lower d33 values, depending on orientation.

Abstract

We report a study of properties of Mn-doped NBT-6%BT single crystals. We show that tetragonal single domain states can be stabilized by poling along a [001] direction. For carefully prepared crystals, the piezoelectric coefficient d33 can reach 570 pC/N. When poled along non-polar directions, the crystals exhibit ferroelectric domain structures consistent with tetragonal micron-sized domains, as revealed by optical observation and Raman spectroscopy. The multidomain crystals have lower d33 values, 225 and 130 pC/N for [011] and [111]-oriented crystals respectively. This trend is commented on from a domain-engineering perspective.