Reporting Excellent Transverse Piezoelectric and Electro‐Optic Effects in Transparent Rhombohedral PMN‐PT Single Crystal by Engineered Domains

Abstract

Transparent ferroelectric crystals with high piezoelectricity are challenging to build because of their complex structure and disordered domains in rhombohedral relaxor ferroelectrics. There are eight domains along the <111> direction, which cause light scattering. In this study, perfect transparency is achieved along the [110] and [001] directions in [110]‐poled rhombohedral 0.72Pb(Mg1/3Nb2/3)O3‐0.28PbTiO3 (PMN‐PT) crystals, which have a high d31 value of 1700 pC N−1 and a high electro‐optic coefficient γ33 of 320 pm V−1. This implies that the [110]‐oriented rhombohedral PMN‐0.28PT crystal can realize the mode of transverse modulation, whereas the [001]‐oriented PMN‐0.28PT crystal is more suitable for the longitudinal mode. Through piezoresponse force microscopy (PFM), it is confirmed that the [110]‐poled rhombohedral PMN‐PT crystals form 71° layered domains, which are similar to the 109° layered domains of the [001]‐oriented transparent crystal. Combined with PFM and birefringence microscopy, the degradation of domains and thickness dependence of piezoelectricity provide clear evidence for the relationship between the engineered domain structures and piezoelectric properties, which should be considered in the design of piezoelectric or electro‐optic devices with excellent performance. This work enriches the research on ferroelectric domain engineering for excellent transparency and high piezoelectricity to provide new ideas for photoacoustic devices.

Magnetic and Magnetostrictive Behaviors of Laves-Phase Rare-Earth—Transition-Metal Compounds Tb1−xDyxCo1.95

“…This observation is consistent with that reported in another MPB-involved system Tb 1−x Dy x Fe 2 [ 39 ]. Interestingly, such a phenomenon was also observed recently in a ferroelectric MPB-involved system [ 40 ].…”

Ferroelectric crystals with giant electro-optic property enabling ultracompact Q-switches

“…Some other ferroelectric materials may also possess high EO coefficients ( r c > 200 pm V −1 ), such as (Sr,Ba)Nb 2 O 6 crystals ( 35 ), but these high values are a result of the ferroelectric phase transition temperature being close to room temperature, which greatly limits their operating temperature range. In addition, the EO coefficients of PIN-PMN-32PT crystals are much higher than that of previously reported relaxor ferroelectric crystals, including 011-poled PMN-28PT ( 21 ). This is due to the following two reasons: First, the composition of PIN-PMN-32PT is closer to the MPB when compared with the reported PMN-28PT.…”

“…The presence of naturally occurring ferroelectric domain walls in the crystals drastically limits their optical transparency as a result of light scattering and reflection at domain walls arising from the difference in refractive indices of the adjacent domains with different orientations, rendering high optical loss or even opacity in the visible-to-near-infrared spectrum. In the past few decades, considerable efforts have been made to eliminate the light-scattering domain walls in these ferroelectrics, but with very limited success ( 13 – 21 ). For example, poling a ferroelectric crystal along its polar direction can achieve a single-domain state without domain walls.…”

Simultaneous Large Optical and Piezoelectric Effects Induced by Domain Reconfiguration Related to Ferroelectric Phase Transitions

“…Though this process achieved good transparency and ultrahigh piezoelectricity, the optical properties of those crystals cannot be easily modulated. Only very recently, Deng et al [31] demonstrated that domainengineered rhombohedral crystals of PMN-PT can have large piezoelectric and electro-optic effects.…”