Phase boundary
View article: Diffusive and Subdiffusive Spin Transport in the Ergodic Phase of a Many-Body Localizable System
Diffusive and Subdiffusive Spin Transport in the Ergodic Phase of a Many-Body Localizable System Open
We study high temperature spin transport in a disordered Heisenberg chain in the ergodic regime. By employing a density matrix renormalization group technique for the study of the stationary states of the boundary-driven Lindblad equation …
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Recent Progress on BaTiO3-Based Piezoelectric Ceramics for Actuator Applications Open
Due to issues with Pb toxicity, there is an urgent need for high performance Pb-free alternatives to Pb-based piezoelectric ceramics. Although pure BaTiO3 material exhibits fairly low piezoelectric coefficients, further designing of such a…
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Scaling Effects in Perovskite Ferroelectrics: Fundamental Limits and Process‐Structure‐Property Relations Open
Ferroelectric materials are well‐suited for a variety of applications because they can offer a combination of high performance and scaled integration. Examples of note include piezoelectrics to transform between electrical and mechanical e…
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Gapped boundary phases of topological insulators via weak coupling Open
The standard boundary state of a topological insulator in 3 + 1 dimensions has gapless charged fermions. We present model systems that reproduce this standard gapless boundary state in one phase, but also have gapped phases with topologica…
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Temperature dependent, large electromechanical strain in Nd-doped BiFeO3-BaTiO3 lead-free ceramics Open
Lead-free piezoceramics with the composition 0.7(Bi1-xNdx)FeO3-0.3BaTiO3+0.1wt% MnO2 (BNxF-BT) were prepared using a conventional solid state route. X-ray diffraction and temperature dependent permittivity measurements indicated a transiti…
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Multifunctional barium titanate ceramics via chemical modification tuning phase structure Open
Global environmental concerns on the toxicity of lead‐based piezoelectrics impel the great mass fervor on investigations of lead‐free alternatives. Barium titanate (BaTiO 3 , BT) ceramics, the first discovered perovskite ferroelectrics, we…
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Understanding, Predicting, and Designing Ferroelectric Domain Structures and Switching Guided by the Phase-Field Method Open
Understanding mesoscale ferroelectric domain structures and their switching behavior under external fields is critical to applications of ferroelectrics. The phase-field method has been established as a powerful tool for probing, predictin…
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Effect of aluminum addition on solid solution strengthening in CoCrNi medium-entropy alloy Open
Solid solution strengthening effect was investigated in AlxCoCrNi medium-entropy alloy (MEA) with different Al content (x = 0–7 at.%). The result of X-ray diffraction indicates that the fully recrystallized phase was a single face-centered…
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Accelerated search for BaTiO <sub>3</sub> -based piezoelectrics with vertical morphotropic phase boundary using Bayesian learning Open
Significance Learning from data to accelerate the discovery of new materials is an outstanding challenge in materials science. However, in addition to data, a distinguishing aspect of materials science is that there exists a substantial bo…
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Machine Learning Out-of-Equilibrium Phases of Matter Open
Neural-network-based machine learning is emerging as a powerful tool for obtaining phase diagrams when traditional regression schemes using local equilibrium order parameters are not available, as in many-body localized (MBL) or topologica…
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Radioactive isotopes reveal a non sluggish kinetics of grain boundary diffusion in high entropy alloys Open
High entropy alloys (HEAs) have emerged as a new class of multicomponent materials, which have potential for high temperature applications. Phase stability and creep deformation, two key selection criteria for high temperature materials, a…
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Topological Phase Transitions in Disordered Electric Quadrupole Insulators Open
We investigate disorder-driven topological phase transitions in quantized electric quadrupole insulators in two dimensions. We show that chiral symmetry can protect the quantization of the quadrupole moment q_{xy}, such that the higher-ord…
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Large Electrocaloric Effect in Relaxor Ferroelectric and Antiferroelectric Lanthanum Doped Lead Zirconate Titanate Ceramics Open
Both relaxor ferroelectric and antiferroelectric materials can individually demonstrate large electrocaloric effects (ECE). However, in order to further enhance the ECE it is crucial to find a material system, which can exhibit simultaneou…
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Thermodynamics and Equations of State of Iron to 350 GPa and 6000 K Open
The equations of state for solid (with bcc, fcc, and hcp structures) and liquid phases of Fe were defined via simultaneous optimization of the heat capacity, bulk moduli, thermal expansion, and volume at room and higher temperatures. The c…
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An assessment of phase field fracture: crack initiation and growth. Open
The phase field paradigm, in combination with a suitable variational structure, has opened a path for using Griffith's energy balance to predict the fracture of solids. These so-called phase field fracture methods have gained significant p…
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Composition and temperature dependence of structure and piezoelectricity in (1−x)(K <sub>1−y</sub> Na <sub>y</sub> )NbO <sub>3</sub> ‐x(Bi <sub>1/2</sub> Na <sub>1/2</sub> )ZrO <sub>3</sub> lead‐free ceramics Open
Lead‐free piezoceramics with the composition (1−x)(K 1− y N a y )NbO 3 ‐x(Bi 1/2 Na 1/2 )ZrO 3 ( KN yN‐ xBNZ ) were prepared using a conventional solid‐state route. X‐ray diffraction, Raman spectroscopy, and dielectric measurements as a fu…
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Role of Reversible Phase Transformation for Strong Piezoelectric Performance at the Morphotropic Phase Boundary Open
A functional material with coexisting energetically equivalent phases often exhibits extraordinary properties such as piezoelectricity, ferromagnetism, and ferroelasticity, which is simultaneously accompanied by field-driven reversible pha…
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Achieving giant electrostrain of above 1% in (Bi,Na)TiO <sub>3</sub> -based lead-free piezoelectrics via introducing oxygen-defect composition Open
Piezoelectric ceramics have been extensively used in actuators, where the magnitude of electrostrain is key indicator for large-stroke actuation applications. Here, we propose an innovative strategy based on defect chemistry to form a defe…
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Active Brownian equation of state: metastability and phase coexistence Open
As a result of the competition between self-propulsion and excluded volume interactions, purely repulsive self-propelled spherical particles undergo a motility-induced phase separation (MIPS).
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Piezoelectric domain walls in van der Waals antiferroelectric CuInP2Se6 Open
Polar van der Waals chalcogenophosphates exhibit unique properties, such as negative electrostriction and multi-well ferrielectricity, and enable combining dielectric and 2D electronic materials. Using low temperature piezoresponse force m…
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Higher-Order Topological Mott Insulators Open
We propose a new correlated topological state, which we call a higher-order topological Mott insulator (HOTMI). This state exhibits a striking bulk-boundary correspondence due to electron correlations. Namely, the topological properties in…
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The Grain Boundary Wetting Phenomena in the Ti-Containing High-Entropy Alloys: A Review Open
In this review, the phenomenon of grain boundary (GB) wetting by melt is analyzed for multicomponent alloys without principal components (also called high-entropy alloys or HEAs) containing titanium. GB wetting can be complete or partial. …
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Enhanced electrocaloric effect near polymorphic phase boundary in lead-free potassium sodium niobate ceramics Open
The electrocaloric (EC) effect in lead-free (1-x)(K0.48Na0.52)(Nb0.95Sb0.05)O3-xBi0.5(Na0.82K0.18)0.5ZrO3 ceramics was investigated using an indirect thermodynamic method. Large EC temperature changes were obtained in the vicinity of a pol…
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Two-Fluid Theory for Spin Superfluidity in Magnetic Insulators Open
We investigate coupled spin and heat transport in easy-plane magnetic insulators. These materials display a continuous phase transition between normal and condensate states that is controlled by an external magnetic field. Using hydrodynam…
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Solving Controversies on the Iron Phase Diagram Under High Pressure Open
As the main constituent of planetary cores, pure iron phase diagram under high pressure and temperature is of fundamental importance in geophysics and planetary science. However, previously reported iron‐melting curves show large discrepan…
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Phase diagram of a disordered higher-order topological insulator: A machine learning study Open
A higher-order topological insulator is a new concept of topological states\nof matter, which is characterized by the emergent boundary states whose\ndimensionality is lower by more than two compared with that of the bulk, and\ndraws a con…
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Peculiarities of the Crystal Structure Evolution of BiFeO3–BaTiO3 Ceramics across Structural Phase Transitions Open
Evolution of the crystal structure of ceramics BiFeO3–BaTiO3 across the morphotropic phase boundary was analyzed using the results of macroscopic measuring techniques such as X-ray diffraction, differential scanning calorimetry, and differ…
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The phase diagram of K<sub>0.5</sub>Na<sub>0.5</sub>NbO<sub>3</sub>–Bi<sub>1/2</sub>Na<sub>1/2</sub>TiO<sub>3</sub> Open
The phase diagram of the lead-free piezoelectric (1 − x )K 0.5 Na 0.5 NbO 3 – x Bi 1/2 Na 1/2 TiO 3 system has been studied by high-resolution synchrotron powder diffraction, neutron powder diffraction and selected area electron diffractio…
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Grain boundary mediated hydriding phase transformations in individual polycrystalline metal nanoparticles Open
Grain boundaries separate crystallites in solids and influence material properties, as widely documented for bulk materials. In nanomaterials, however, investigations of grain boundaries are very challenging and just beginning. Here, we re…
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Structural transformations and physical properties of (1 − <i>x</i>) Na<sub>0.5</sub>Bi<sub>0.5</sub>TiO<sub>3</sub> − <i>x</i> BaTiO<sub>3</sub> solid solutions near a morphotropic phase boundary Open
Piezoelectric and other physical properties are significantly enhanced at (or near) a morphotropic phase boundary (MPB) in ferroelectrics. MPB materials have attracted significant attention owing to both fundamental physics as well as the …