Controllable Ferroelastic Switching in Epitaxial Self-Assembled Aurivillius Nanobricks

Abstract

Layered perovskites with Aurivillius phase have drawn tremendous attention recently, owing to their high ferroelectric Curie temperatures, large spontaneous polarization, and fatigue-free and environment-friendly characteristics. Bi2WO6 is one of the simplest members in the Aurivillius family with superior ferroelastic and photo-electrochemical behaviors. The self-assembly fabrication of its nanoarchitectures and strategic modulation of their ferroelastic switching are crucial toward highly efficient nanoscale applications. In this work, Bi2WO6 nanobrick arrays were epitaxially grown along the orthorhombic direction in a self-assembled way. Such a nanoscale topology supports out-of-plane and in-plane vectors of ferroelectric polarizations, enabling a perpendicular voltage manipulation of these emerging ferroelectric/elastic domains. Combining the scanning probe technique and transmission electron microscopy, we confirmed the in-plane polarization vectors of 78.6 and 101.4° within the crystallographic axes of the nanobricks with respect to the (110) plane of the substrate. Thus, this work provides new opportunities for ferroelectric/elastic engineering in Bi2WO6 nanostructures for a wide range of applications, such as sensing, actuating, and catalysis.

Lanthanide Ion-Doped Bismuth Titanate Nanocomposites for Ratiometric Thermometry with Low Pump Power Density

“…On the other hand, Yb 3+ is usually doped into optical materials as a sensitizer to enhance absorption at 980 nm. There is an efficiency resonance between the 2 F 5/2 of Yb 3+ ion and the 4 I 11/2 of Er 3+ ion, which enables excellent energy transfer between Yb 3+ and the adjacent Er 3+ ions. − This is expected to be Yb 3+ /Er 3+ -codoped upconversion green light emission for temperature measurement under low-power 980 nm laser excitation.…”

Deterministic reversal of single magnetic vortex circulation by an electric field

“…This gives us a hint that a spacevarying strain (dynamic motion) may be effective to reverse the magnetic vortex circulation deterministically. The reversible inplane ferroelastic switching with a non-volatile strain of approximately 0.4% in layered-perovskite Bi 2 WO 6 (BWO) thin films indicates that BWO thin films are potential for magnetoelectronic applications and appropriately provide a prototype platform to achieve the considerable planar space-varying strain by electric field [31,32].…”

Strain-Engineered Ferroelastic Structures in PbTiO3 Films and Their Control by Electric Fields

“…This makes the ferroelastic structures attractive for novel applications in reconfigurable electronics. Additionally, ferroelastic switching and generation of user-defined ferroelastic–ferroelectric structures by an electric field , can provide new methodologies for (nano-)­electromechanics and piezoelectric devices. , On the other hand, the electrical switching of ferroelastic structures in epitaxial films may be impeded by elastic constrains imposed by the substrate − or their elastic pinning to defects, making the ferroelastic domain walls less mobile than their exclusive ferroelectric or magnetic counterparts. It is thus essential to not only engineer new ferroelastic structures but also assess the feasibility of the electric field control of these structures and their stability over time.…”