Related papers: Quantum-Geometric Origin of Out-of-plane Stacking …
Two-dimensional (2D) ferroelectrics, which is rare in nature, enable high-density non-volatile memory with low energy consumption. Here, we propose a theory of bilayer stacking ferroelectricity (BSF), in which, two stacked layers of the…
2D ferroelectrics with robust polarization down to atomic thicknesses provide novel building blocks for functional heterostructures. Experimental reports, however, remain scarce because of the requirement of a layered polar crystal. Here,…
Ferroelectricity in atomically thin bilayer structures has been recently predicted1 and measured[2-4] in two-dimensional (2D) materials with hexagonal non-centrosymmetric unit-cells. Interestingly, the crystal symmetry translates lateral…
Piezoelectric and ferroelectric properties in the two dimensional (2D) limit are highly desired for nanoelectronic, electromechanical, and optoelectronic applications. Here we report the first experimental evidence of out-of-plane…
Stacking nonpolar, monolayer materials has emerged as an effective strategy to harvest ferroelectricity in two-dimensional (2D) van de Waals (vdW) materials. At a particular stacking sequence, interlayer charge transfer allows for the…
The combination of metallicity and ferroelectricity breaks traditional boundaries, paving new avenues for innovative electronic materials and devices. This breakthrough is particularly notable, as metallicity and ferroelectricity have…
Sliding ferroelectricity is a phenomenon that arises from the insurgence of spontaneous electronic polarization perpendicular to the layers of two-dimensional (2D) systems upon the relative sliding of the atomic layer constituents. Because…
Despite their ionic nature, many layered diatomic crystals avoid internal electric polarization by forming a centrosymmetric lattice at their optimal anti-parallel van-der-Waals stacking. Here, we report a stable ferroelectric order…
Electric polarization typically originates from non-centrosymmetric charge distributions in compounds. In elemental crystalline materials, chemical bonds between atoms of the same element favor symmetrically distributed electron charges and…
Although multiferroics have undergone extensive examination for several decades, the occurrence of ferroelectricity induced by orbital order is only scarcely documented. In this study, we propose the existence of spontaneous ferroelectric…
Two-dimensional sliding ferroelectrics, with their unique stacking degrees of freedom, offer a different approach to manipulate polarization by interlayer sliding. Bending sliding ferroelectrics inevitably leads to interlayer sliding…
The first switchable electric polarization in metals was recently discovered in bilayer and trilayer WTe2. Strangely, despite the tininess of the ordered polarization, the ferroelectricity survives up to 350 K, rendering the mechanism of…
Ferroelectricity (Valasek, J. Phys. Rev. 1921, 17, 475) - a spontaneous formation of electric polarisation - is a solid state phenomenon, usually, associated with ionic compounds or complex materials. Here we show that, atypically for…
Van der Waals (vdW) materials have greatly expanded our design space of heterostructures by allowing individual layers to be stacked at non-equilibrium configurations, for example via control of the twist angle. Such heterostructures not…
Recent studies have reported emergent ferroelectric behavior in twisted or moir\'e-engineered graphene-based van der Waals heterostructures, yet the microscopic origin of this effect remains under debate. Pristine mono- or few-layer…
The bistability of charge polarization in ferroelectric materials has long been the basis of ferroelectric devices. However, the ferroelectricity tends to be vanishing as the thickness of materials is reduced to a few nanometers or thinner…
Two-dimensional (2D) ferroelectric (FE) materials are promising compounds for next-generation nonvolatile memories, due to their low energy consumption and high endurance. Among them, {\alpha}-In$_{2}$Se$_{3}$ has drawn particular attention…
Ferroelectricity is usually found in compound materials composed by different elements. Here, based on first-principles calculations, we reveal the first example of spontaneous electrical polarization and ferroelectricity in stable…
Ferroelectricity, a hallmark of spontaneous inversion-symmetry breaking, has been a central concept in condensed matter physics and functional materials research, yet recent discoveries are revealing that switchable polarization can emerge…
Van der Waals "sliding" ferroelectric bilayers, whose electric polarization is locked to the interlayer alignment, show promise for future non-volatile memory and other nanoelectronic devices. These applications require a fuller…