Symmetry Strategy for Rapid Discovery of Abundant Fractional Quantum Ferroelectrics

Physical Review Letters, Journal Year: 2025, Volume and Issue: 134(1)

Published: Jan. 8, 2025

Traditional ferroelectrics are limited by Neumann's principle, which confines exploration of within polar point groups. Our recent work [Ji et al., Nat. Commun. 15, 135 (2024)NCAOBW2041-172310.1038/s41467-023-44453-y] proposes the concept fractional quantum ferroelectricity (FQFE) that extends playground to nonpolar Here, we apply group theory and introduce an efficient symmetry strategy identify FQFE candidates. Integrated with a high-throughput screening scheme, go through 171 527 materials 221 potential candidates, already experimentally synthesized. In addition, out for first time essence is atomic displacements respect lattice vectors, can actually result in both (type I) integer II) quantized polarization, respectively. Through performing first-principles calculations, verify symmetry-predicted switchable properties bulk AlAgS_{2} monolayer HgI_{2}. Notably, exhibits ultralow switching barrier 22 meV/f.u. interlocked in-plane/out-of-plane while HgI_{2} displays large spontaneous polarization 42 μC/cm^{2}. findings not only advance understanding on FQFE, but also offer guidance experimental design novel ferroelectric materials.

Language: Английский

---

Unconventional (anti)ferroelectricity in van der Waals group-IV monochalcogenides

Nature Communications, Journal Year: 2025, Volume and Issue: 16(1)

Published: Feb. 20, 2025

Fundamentally, ferroelectrics must belong to a noncentrosymmetric space group, limiting the exploration of more new ferroelectric materials. We circumvent this limitation by triggering structure distortion and inducing ferroelectricity in centrosymmetric van der Waals group-IV monochalcogenide GeSe semiconductor that features unexpected intrinsic out-of-plane antiferroelectricity. Double-type single-type hysteresis loops from electric measurements, bonding observed in-situ atomic imaging, perpendicular polarization uncovered first-principles calculations, confirm antiferroelectricity antiferroelectric-ferroelectric transition induced vertical external electric-field. The hidden field spatial-inversion symmetric makes it member layered semiconductors with both in-plane ferroelectricity, possibly, can be extended all monochalcogenides other

Language: Английский

---

Quantum secure authentication and key agreement protocols for IoT-enabled applications: A comprehensive survey and open challenges

Computer Science Review, Journal Year: 2024, Volume and Issue: 54, P. 100676 - 100676

Published: Aug. 31, 2024

Language: Английский

---

Dynamics of ferroelectricity in monolayer AgCr2S4 calculated with a machine learning potential

Physical review. B./Physical review. B, Journal Year: 2025, Volume and Issue: 111(8)

Published: Feb. 18, 2025

Language: Английский

---

Ultralow-pressure mechanical-motion switching of ferroelectric polarization

Science Advances, Journal Year: 2025, Volume and Issue: 11(18)

Published: May 1, 2025

Ferroelectric polarization switching, achieved by mechanical forces, enables the storage of stress information in ferroelectrics and holds promise for human interface applications. The prevailing approach is locally induced flexoelectricity with large strain gradients. However, this usually requires huge which greatly impede device Here, we report an using triboelectric effect to mechanically, reversibly switch ferroelectric across α-In2Se3 memristors. Through contact electrification electrostatic induction effects, units are used sensitively detect forces generate electrical voltage pulses trigger resistance switching. We realize multilevel states under different a neuromorphic system demonstrated. Notably, achieve reversal record-low force ~10 kilopascals even tactile touches. Our work provides fundamental but pragmatic strategy creating memory devices.

Language: Английский

---

DFSE: Inverse Design of Ferroelectrics from Spatial Symmetry Breaking Evolution

Journal of Chemical Theory and Computation, Journal Year: 2025, Volume and Issue: unknown

Published: May 8, 2025

Discovering new ferroelectric materials is essential to overcoming the limitations of existing compounds, enabling innovative applications, advancing scientific understanding, and promoting environmental sustainability technological progress. Symmetry fundamental existence ferroelectricity, furthermore, ferroelectricity inherently requires breaking spatial inversion symmetry induce spontaneous polarization. In this article, we introduce DFSE (Design Ferroelectrics from Spatial Breaking Evolution), a symmetry-guided inverse design software for in 3D or 2D form with specific element ratios. embodies novel paradigm that systematically induces through controlled breaking. The workflow begins by generating centrosymmetric parent phases (space groups selected mapping table) then introduces targeted atomic displacements break symmetry, including single-atom random axis, two-atom plane displacement patterns fractional quantum ferroelectrics. This symmetry-breaking evolution directly correlated emergence Potential candidates are after verifying influence using first-principles calculations. Tests have been run on multiple systems In2Se3 HfO2 PbTiO3, it has proved highly efficient reliable discovering materials.

Language: Английский

---

Sign of the piezoelectric response in double-path ferroelectrics

Physical review. B./Physical review. B, Journal Year: 2025, Volume and Issue: 111(18)

Published: May 9, 2025

Language: Английский

---

Intrinsic Sliding Ferroelectricity and High‐Quality Superlinear Emission in Van der Waals γ‐InSe Semiconductor

Advanced Functional Materials, Journal Year: 2025, Volume and Issue: unknown

Published: May 23, 2025

Abstract High‐quality single crystals are the fundamental foundation for advancing 2D van der Waals (vdW) layered semiconductors toward applications in low‐consumptive nanodevices. The easily formed stacking faults (SFs) vdW materials hide intrinsic optical/electrical properties, adverse to practical application. Here, a unique low‐temperature annealing strategy is adopted eliminate SFs flexible γ‐InSe and optimize crystal quality. annihilation dynamics of revealed by using situ heating observation on state‐of‐the‐art spherical aberration‐corrected transmission electron microscopy. annealed not only exhibits out‐of‐plane sliding ferroelectricity wide thickness range from unit cell (trilayer) tens nanometers, but also demonstrates efficient superlinear photoluminescence with higher beam quality lower thresholds. This should expedite near infrared emitter lasing, in‐memory computing, ferroelectric photovoltaics or detectors.

Language: Английский

---

Ferroelectricity with Long ion Displacements in Crystals of Non‐Polar Point Groups

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: unknown

Published: May 13, 2024

Abstract In the classical model, ferroelectricity is associated with small ion displacements from paraelectric phases high symmetry, and ferroelectric crystals must adopt one of ten polar point groups low symmetry according to Neumann's principle. this work, it proposed that conclusion based on perfect bulk without taking boundaries into account. First‐principles evidence shows polarizations may also be formed in some non‐polar as edges generally break crystal symmetry. Meanwhile, such can maintained at macroscale are switchable when transition between multiple equivalent states realized via long displacements， essentially akin conductors. For example, switching barriers much reduced sliding bilayer systems or ionic compounds covalent‐like directionality. Such unconventional attributed displacements, its existence several like CuCrS 2 supported by experimental observations. It explain a series unclarified phenomena reported previously well significantly expand scope ferroelectrics, especially those induced displacements.

Language: Английский

---

Ferroelectricity induced by lone pair electron effect in halide perovskite monolayers

Physical review. B./Physical review. B, Journal Year: 2024, Volume and Issue: 110(3)

Published: July 16, 2024

Two-dimensional (2D) ferroelectricity has attracted considerable interest since its demonstration in van der Waals monolayers. Research on 2D so far focused materials, and whether some of the intrinsic ferroelectric mechanisms found perovskite bulks can be retained to monolayer limit remains an issue solved. Here, we demonstrate that caused by lone pair electron effect exist inorganic halide This occurs monolayers with smaller anions, involving ${\mathrm{Cs}}_{2}{\mathrm{GeF}}_{4}, {\mathrm{Cs}}_{2}{\mathrm{SnF}}_{4}$, ${\mathrm{Cs}}_{2}{\mathrm{SnCl}}_{4}$. The first two are direct band-gap semiconductors while latter is indirect semiconductor. octahedral tilt mode also appears ground-state structures these ferroelectrics. containing ${\mathrm{F}}^{\ensuremath{-}}$ ions have relatively greater polarization, but a higher-energy barrier for switching. work helps design beyond materials.

Language: Английский

---