A5080534308- Ferroelectric and Piezoelectric Materials
- Multiferroics and related materials
- Acoustic Wave Resonator Technologies
- Electronic and Structural Properties of Oxides
- Magnetic and transport properties of perovskites and related materials
- Solid-state spectroscopy and crystallography
- Adhesion, Friction, and Surface Interactions
- Advancements in Solid Oxide Fuel Cells
- 2D Materials and Applications
- Dielectric materials and actuators
- MXene and MAX Phase Materials
- Graphene research and applications
- Mechanical and Optical Resonators
- Silicon and Solar Cell Technologies
- Semiconductor materials and devices
- Surface Roughness and Optical Measurements
- Perovskite Materials and Applications
- Smart Materials for Construction
- Advanced MEMS and NEMS Technologies
- Advanced Condensed Matter Physics
- Ultrasonics and Acoustic Wave Propagation
- Advanced Surface Polishing Techniques
- Electrical and Thermal Properties of Materials
Institut de Ciència de Materials de Barcelona
2019-2024
University of Liège
2024
Université de Bordeaux
2017-2021
Centre National de la Recherche Scientifique
2017-2021
Institut de Chimie de la Matière Condensée de Bordeaux
2017-2021
Instituto de Ciencia de Materiales de Sevilla
2020
École Polytechnique Fédérale de Lausanne
2014-2016
Use of ferroelectric domain-walls in future electronics requires that they are stable, rewritable conducting channels. Here we demonstrate nonthermally activated metallic-like conduction nominally uncharged, bent, ferroelectric-ferroelastic the ubiquitous Pb(Zr,Ti)O3 using scanning force microscopy down to a temperature 4 K. New walls created at K by pressure exhibit similar robust and intrinsic conductivity. Atomic resolution electron energy-loss spectroscopy confirms conductivity...
Diverse topological defects arise in hexagonal manganites, such as ferroelectric vortices, well neutral and charged domain walls. The are intriguing because their low symmetry enables unusual couplings between structural, charge, spin degrees of freedom, holding great potential for novel types functional 2D 1D systems. Despite the considerable advances analyzing different understanding key intrinsic properties is still rather limited disconnected. In particular, a rapidly increasing number...
Although ferroelectric materials are characterised by their parallel arrangement of electric dipoles, in the right boundary conditions these dipoles can reorganize themselves into vortices, antivortices and other non-trivial topological structures. By contrast, little is known about how (or whether) antiferroelectrics, which showing an antiparallel exhibit vortices or antivortices. In this study, using advanced aberration-corrected scanning transmission electron microscopy, we uncover...
Layered oxides exhibit high ionic mobility and chemical flexibility, attracting interest as cathode materials for lithium-ion batteries the pairing of hydrogen production carbon capture. Recently, layered emerged highly tunable semiconductors. For example, by introducing anti-Frenkel defects, electronic hopping conductance in hexagonal manganites was increased locally orders magnitude. Here, we demonstrate local acceptor donor doping Er(Mn,Ti)O$_3$, facilitated splitting such defects under...
Low-temperature electrostatic force microscopy (EFM) is used to probe unconventional domain walls in the improper ferroelectric semiconductor Er0.99Ca0.01MnO3 down cryogenic temperatures. The low-temperature EFM maps reveal pronounced electric far fields generated by partially uncompensated domain-wall bound charges. Positively and negatively charged display qualitatively different as a function of temperature, which we explain based on screening mechanisms corresponding relaxation time...
Ferroelectric domain walls are quasi-2D systems that show great promise for the development of nonvolatile memory, memristor technology, and electronic components with ultrasmall feature size. Electric fields, example, can change wall orientation relative to spontaneous polarization switch between resistive conductive states, controlling electrical current. Being embedded in a 3D material, however, not perfectly flat form networks, which leads complex physical structures. In this work,...
We reveal a strong elastic interaction between nonferroelastic domain walls in ferroelectric thin films. This interaction, having no analogue bulk materials, is governed by fields that are associated with the and extends to distances comparable film thickness. Such widening of shown be particularly common perovskites. The results especially relevant for control wall propagation understanding polarization dynamics.
Domain walls separating regions of opposite polarity in ferroelectric materials are mechanically softer than the domains they separate, a result that extends distinct physics domain to their mechanical properties.
Properties of ferroelectric domain walls are attractive for future nano- and optoelectronics. An important element is the potential to electrically erase/rewrite inside working devices. Dense wall patterns, formed upon cooling through phase transition, were demonstrated. However, room temperature writing done with a cantilever tip, one stripe at time, reduction inter-wall distance limited by tip diameter. Here, we show, temperature, controlled formation arrays sub-tip-diameter spacing (i.e.,...
Abstract Spin-spiral multiferroics exhibit a magnetoelectric coupling effects, leading to the formation of hybrid domains with inseparably entangled ferroelectric and antiferromagnetic order parameters. Due this strong coupling, conceptually advanced ways for controlling antiferromagnetism become possible it has been reported that electric fields laser pulses can reversibly switch order. This switching spin textures is great interest emergent field spintronics. Established approaches,...
Antiphase boundaries (APBs) are unique domain walls that may demonstrate switchable polarization in otherwise non-ferroelectric materials such as SrTiO3 and PbZrO3. The current study explores the possibility of displacing at nanoscale. We suggest manipulating APBs using inhomogeneous electric field an Atomic Force Microscopy (AFM) tip with applied voltage placed their proximity. displacement is studied a function voltage, film thickness, initial separation AFM from APB. It established, for...
Though antiferroelectricity in PbZrO${}_{3}$ was discovered over 70 years ago, there is still no consensus on the exact physical mechanism behind its formation. In this study, authors rationalize antiferroelectric $P\phantom{\rule{0}{0ex}}b\phantom{\rule{0}{0ex}}a\phantom{\rule{0}{0ex}}m$ state of as a modulated phase, where polarization and antiphase O${}_{6}$ octahedra tilts are coupled via trilinear gradient term -- so-called rotopolar coupling. A Landau-like continuum Hamiltonian, with...
Low-temperature X-ray photoemission electron microscopy (X-PEEM) is used to measure the electric potential at domain walls in improper ferroelectric Er0.99Ca0.01MnO3. By combining X-PEEM with scanning probe and theory, we develop a model that relates detected contrast emergence of uncompensated bound charges, explaining image formation based on intrinsic electronic domain-wall properties. In previously applied low-temperature electrostatic force (EFM), readily distinguishes between positive...
Moiré superlattices in van der Waals (vdW) heterostructures have given rise to a number of emergent electronic phenomena due the interplay between atomic structure and electron correlations. A lack simple way characterize moiré has impeded progress field. In this work we outline simple, room-temperature, ambient method visualize real-space with sub-5 nm spatial resolution variety twisted vdW including but not limited conducting graphene, insulating boron nitride semiconducting transition...
Abstract The intrinsic mobile interfaces in ferroelectrics—the domain walls can drive and enhance diverse ferroelectric properties, essential for modern applications. Control over the motion of is high practical importance. Here we analyse theoretically show experimentally epitaxial films, where coexist interact with immobile growth-induced interfaces—columnar boundaries. Whereas these boundaries do not disturb long-range crystal order, they affect behaviour a peculiar selective manner....
Recent developments in the physics of non-magnetic ferroics identified possible functionality domain walls these materials, which specifies current interest to internal structure walls. In this context, wall thickness itself can be regarded as an important parameter functional elements, raising following questions. How thick ferroelectric be? To what extent their controlled? answering questions, we discuss mechanisms controlling for different types Besides, provide overview recent results on...
Lead-free antiferroelectric perovskite $\rm AgNbO_3$ is nowadays attracting extensive research interests due to its promising applications in energy storage. Although great progress has been made optimizing the material performance, fundamental questions remain regarding mechanism stabilizing $Pbcm$ phase. Here, combining structural symmetry analysis and first-principles calculations, we identified crucial anharmonic couplings of oxygen octahedra rotations cation antipolar motions which...
Lead-free antiferroelectric perovskite ${\mathrm{AgNbO}}_{3}$ is nowadays attracting extensive research interests due to its promising applications in energy storage. Although great progress has been made optimizing the material performance, fundamental questions remain regarding mechanism stabilizing $Pbcm$ phase. Here, combining structural symmetry analysis and first-principles calculations, we identified crucial anharmonic couplings of oxygen octahedra rotations cation antipolar motions...
Ferroelectric domain walls are a rich source of emergent electronic properties and unusual polar order. Recent studies show that the configuration ferroelectric can go well beyond conventional Ising-type structure. Néel-, Bloch-, vortex-like patterns have been observed, displaying strong similarities with spin textures at magnetic walls. Here, discovery antiferroelectric in uniaxial Pb
Ferroelectric domain walls are quasi-2D systems that show great promise for the development of non-volatile memory, memristor technology and electronic components with ultra-small feature size. Electric fields, example, can change wall orientation relative to spontaneous polarization switch between resistive conductive states, controlling electrical current. Being embedded in a 3D material, however, not perfectly flat form networks, which leads complex physical structures. We demonstrate...