Mechanical force-induced interlayer sliding in interfacial ferroelectrics

Nature Communications, Год журнала: 2025, Номер 16(1)

Опубликована: Янв. 24, 2025

Moiré superlattices in two-dimensional stacks have attracted worldwide interest due to their unique electronic properties. A typical example is the moiré ferroelectricity, where adjacent moirés exhibit opposite spontaneous polarization that can be switched through interlayer sliding. However, contrast ideal regular ferroelectric domains (equilateral triangles) built most theoretical models, unavoidable irregular supercells (non-equilateral induced by external strain fields during transfer process been given less attention. Manipulation of controllable evolutions also a big challenge an interlinked network polarized domains. In this study, we employ sliding-disturb measurement examine and modulate these via mechanical force. By introducing curved substrate, are fabricated, three distinct types with different patterns identified modulated force disturbing. They reduced pinning forces when shear direction not aligned direction. The shift observed orthogonal This work offers effective pathway for controlled switch interfacial ferroelectricity. challenge. authors fabricate moirés, identifying patterns, modulating them

Язык: Английский

---

Sliding ferroelectricity in two-dimensional materials and device applications

Materials Science and Engineering R Reports, Год журнала: 2025, Номер 163, С. 100927 - 100927

Опубликована: Янв. 11, 2025

Язык: Английский

---

Chemifriction and Superlubricity: Friends or Foes?

The Journal of Physical Chemistry Letters, Год журнала: 2025, Номер unknown, С. 2934 - 2941

Опубликована: Март 13, 2025

The mechanisms underlying chemifriction (the contribution of interfacial bonding to friction) in defected twisted graphene interfaces are revealed using fully atomistic molecular dynamics simulations based on machine-learning potentials. This involves stochastic events consecutive bond formation and rupture between single vacancy defects that may enhance friction. A unique shear-induced interlayer atomic transfer healing mechanism is discovered can be harnessed design a run-in procedure restore superlubric sliding. should manifested as negative differential friction coefficients expected emerge under moderate normal loads. physically motivated phenomenological model developed predict the effects experimentally relevant sliding velocity regimes. allows us identify distinct transition logarithmic increase decrease force with increasing velocity. While demonstrated for homogeneous graphitic contacts, similar occur other or heterogeneous two-dimensional material interfaces.

Язык: Английский

---

Striped Twisted State in the Orientational Epitaxy on Quasicrystals

Physical Review Letters, Год журнала: 2025, Номер 134(6)

Опубликована: Фев. 12, 2025

The optimal "twisted" geometry of a crystalline layer on crystal has long been known, but that quasicrystal is still unknown and open. We predict analytically the equilibrium configuration will generally exhibit nonzero misfit angle. theory perfectly agrees with numerical optimization colloid monolayer quasiperiodic decagonal optical lattice. Strikingly different from crystal-on-crystal epitaxy, structure novel emerging twisted state exhibits an unexpected stripe pattern. Its high anisotropy should reflect tribomechanical properties this unconventional interface.

Язык: Английский

---

Mechanisms of Strain-Dependent Interlayer Dynamic Friction in Graphene

ACS Applied Materials & Interfaces, Год журнала: 2025, Номер unknown

Опубликована: Март 17, 2025

Two-dimensional materials have now become the main components of nanoelectromechanical systems due to their outstanding properties in practical application. This study investigates dynamic friction between rotational graphene layers under equi-biaxial tensile and shear strain via molecular dynamics simulations from perspective energy dissipation. To eliminate influence commensurability edge effect, a pair model with annular as slider is established. The mechanisms effect coupling temperature, frequency, supporting stiffness on interlayer are analyzed. results indicate that reduces friction, while varies temperature. mechanism frictional dissipation explained perspectives interface moiré pattern, entropic interatomic interactions, effective contact atoms, in-plane deformation, out-of-plane lattice vibration, phonon state density. research will provide theoretical basis for design manipulation two-dimensional materials.

Язык: Английский

---

Structural superlubric slidevices

Device, Год журнала: 2025, Номер unknown, С. 100745 - 100745

Опубликована: Март 1, 2025

---

Probing Fracture Mechanics of Graphene through Heterocrack Propagation in a Moiré Superlattice

Journal of the Mechanics and Physics of Solids, Год журнала: 2025, Номер unknown, С. 106151 - 106151

Опубликована: Апрель 1, 2025

Язык: Английский

---

Ultrahigh Thermal Conductance across Superlubric Interfaces in Twisted Graphite

Physical Review Letters, Год журнала: 2025, Номер 134(14)

Опубликована: Апрель 11, 2025

Interlayer rotation in van der Waals (vdW) materials offers a unique degree of freedom for manipulating lattice dynamics and leads to an exotic state with vanishing friction called structural superlubricity. Extensive theoretical calculations have also predicted the potential twisted vdW controlling heat flow advanced electronics. However, precise experimental measurements proven extremely challenging only handful efforts date reporting inconsistent results. Here, we managed achieve simultaneous mechanical characterizations thermal intrinsic interfaces microfabricated graphite mesas. Remarkably, conductance superlubric reaches about 600 MWm^{-2} K^{-1} which surpasses measured values artificially stacked structures by nearly order magnitude. Nonetheless, successfully resolved over 30-fold variation as buried were rotated locked state. Further, atomic simulations revealed predominant role transverse acoustic phonons. Together, our findings highlight general physical picture that directly correlates interfacial transport sliding resistance, lay foundation twist-enabled management are particularly beneficial twistronics slidetronics.

Язык: Английский

---

Scaling‐Up of Structural Superlubricity: Challenges and Opportunities

Advanced Functional Materials, Год журнала: 2025, Номер unknown

Опубликована: Апрель 14, 2025

Abstract Structural superlubricity (SSL) at layered material interfaces is an exciting and vibrant field of research, offering vast opportunities to achieve ultralow friction wear with numerous potential technological applications. At increasing length‐scales, new physical chemical energy dissipation pathways emerge that threaten push the system out superlubric regime. Physical inhibitors SSL are primarily associated in‐plane elasticity, out‐of‐plane corrugation, moiré superlattices, grain boundaries, lattice defects. Chemical mechanisms may suppress behavior include interlayer bonding, wear, external contaminants. In this article, these other challenges reviewed facing scaling‐up structural superlubricity, as reflected in recent experimental theoretical studies. Further perspectives offered on future directions for realizing manipulating macroscale outlining it entails.

Язык: Английский

---

High-quality-factor viscoelastic nanomechanical resonators from moiré superlattices

Nature Communications, Год журнала: 2025, Номер 16(1)

Опубликована: Апрель 22, 2025

The moiré superlattice, created by stacking van der Waals layered materials with rotational misalignments, exhibits a multitude of emergent correlated phenomena ranging from superconductivity to Mott insulating states. In addition exotic electronic states, the intricate networks incommensurate lattices may give rise polymer-like viscoelasticity, which combines properties both elastic solids and viscous fluids. This phenomenon enrich dynamics nanomechanical resonators, in viscoelasticity has not played role thus far. Here, we report on controllable hysteretic response vibrations twisted bilayer graphene membranes, attribute viscoelasticity. Accompanying this response, measure unusually large mechanical quality factors Q reaching remarkably high value ~1900 at room temperature. We interpret enhancement as signature dissipation dilution, considerable interest that recently been harnessed quantum optomechanical systems. Viscoelasticity features "lossless" potential overcomes corrugation registry reinforces such dilution. Our work introduces superlattice promising system for engineering through rotating angles observing nanoelectromechanical couplings.

Язык: Английский

---