Electric field tunable bands in a doubly aligned bilayer graphene hBN moiré superlattice DOI
Priya Tiwari, Kenji Watanabe, Takashi Taniguchi

et al.

Physical review. B./Physical review. B, Journal Year: 2024, Volume and Issue: 110(23)

Published: Dec. 12, 2024

In this letter, we demonstrate electric field-induced band modification of an asymmetrically twisted hBN/BLG/hBN supermoire lattice. Distinct from unaligned BLG/hBN systems, observe regions in the density-displacement field (n-D) plane where device conductance is independent n and decreases as |D| increases. This distinction arises due to angle asymmetry between layers, which induces field-controlled layer polarization. We identify D-dependent additional gaps near charge neutrality point that appear conduction (valence) for negative (positive) D values. quantum Hall regime, new 6-fold degenerate Landau levels are observed. Our findings establish asymmetric heterostructure, external vertical displacement affects valence bands very differently sheds light on patterns noted previous studies.

Language: Английский

Emergence of radial Rashba spin-orbit fields in twisted van der Waals heterostructures DOI
Tobias Frank, Paulo E. Faria, Klaus Zollner

et al.

Physical review. B./Physical review. B, Journal Year: 2024, Volume and Issue: 109(24)

Published: June 12, 2024

The Rashba effect is quintessential in condensed matter physics, appearing virtually any electronic heterostructure. Its well-known manifestation a tangential spin texture. Here, the authors theoretically demonstrate emergence and engineering of radial textures twisted van der Waals heterostructures using rigorous first-principles simulations phenomenological modeling. These predictions offer new opportunities for controlling manipulation, as well tuning correlated states superconductivity realm.

Language: Английский

Citations

12
Experimental signature of layer skyrmions and implications for band topology in twisted WSe2 bilayers DOI
Fan Zhang, Nicolás Morales-Durán, Yanxing Li

et al.

Nature Physics, Journal Year: 2025, Volume and Issue: unknown

Published: May 1, 2025

Language: Английский

Citations

1
Polar and quasicrystal vortex observed in twisted-bilayer molybdenum disulfide DOI
Chi Shing Tsang, Xiaodong Zheng, Tong Yang

et al.

Science, Journal Year: 2024, Volume and Issue: 386(6718), P. 198 - 205

Published: Oct. 10, 2024

We report the observation of an electric field in twisted-bilayer molybdenum disulfide (MoS

Language: Английский

Citations

9
Unified deep learning network for enhanced accuracy in predicting thermal conductivity of bilayer graphene, hexagonal boron nitride, and their heterostructures DOI Creative Commons
Rongkun Chen, Yu Tian, Jiayi Cao

et al.

Journal of Applied Physics, Journal Year: 2024, Volume and Issue: 135(14)

Published: April 12, 2024

In this research, we utilized density functional theory (DFT) computations to perform ab initio molecular dynamics simulations and static calculations on graphene, hexagonal boron nitride, their heterostructures, subjecting them strains, perturbations, twist angles, defects. The gathered energy, force, virial information informed the creation of a training set comprising 1253 structures. Employing Neural Evolutionary Potential framework integrated into Graphics Processing Units Molecular Dynamics, fitted machine learning potential (MLP) that closely mirrored DFT energy surface. Rigorous validation lattice constants phonon dispersion relations confirmed precision dependability MLP, establishing solid foundation for subsequent thermal transport investigations. A further analysis impact angles uncovered significant reduction in conductivity, particularly notable heterostructures with decline exceeding 35%. conductivity primarily stems from angle-induced softening modes accompanying increase scattering rates, which intensifies anharmonic interactions among phonons. Our study underscores efficacy MLP delineating attributes two-dimensional materials while also elucidating micro-mechanisms behind influence angle offering fresh perspectives design advanced management materials.

Language: Английский

Citations

6
Robust flat bands in twisted trilayer graphene moiré quasicrystals DOI Creative Commons

Chen-Yue Hao,

Zhen Zhan, Pierre A. Pantaleón

et al.

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: Sept. 30, 2024

Language: Английский

Citations

6
Global minimum structures and electronic properties variation of hydrogen adatoms on/in H-phase MX2 ( M=Mo , W; X<… DOI
Kexin Hou, Rui Yang, Nuo Xu

et al.

Physical review. B./Physical review. B, Journal Year: 2025, Volume and Issue: 111(4)

Published: Jan. 15, 2025

Although hydrogen is almost always present in the growth environments of two-dimensional (2D) transition metal dichalcogenides (TMDs), there a lack global structure search atoms on different TMDs as well corresponding electronic properties variation and underlying mechanisms for properties. A atom in/on monolayer (ML) H-phase MX2 (M = Mo, W; X S, Se, Te) can be an interstitial (HInt) or adatom either vertically (HVert) tilted above (HTilt) atom. In this paper, scanning adsorption structures on/in MX2's shows that most stable with MoS2 WS2 HTilt due to repulsion between lone-pair electrons sulfur hydrogen-sulfur bonding electrons, while MoSe2, WSe2, MoTe2, HInt becomes favored larger lattice constant these TMDs. Both introduce fully spin-polarized levels close conduction band but have origins spin polarization M atoms, gaining losing structures, respectively. The special case which does not exhibit electron delocalization. Moreover, diffusion barrier analyses adatoms indicate from relatively slow process at room temperature. we broaden understanding clarify several interaction MX2's. These insights are vital importance various applications such (opto)electronics, spintronics, catalysis. locked icon Physics Subject Headings (PhySH)AdsorptionElectronic structure2-dimensional systemsTransition dichalcogenidesMagnetic momentDensity functional calculationsFirst-principles calculations

Language: Английский

Citations

0
Colloquium : Synthetic quantum matter in nonstandard geometries DOI
Tobias Graß, Dario Bercioux, Utso Bhattacharya

et al.

Reviews of Modern Physics, Journal Year: 2025, Volume and Issue: 97(1)

Published: March 25, 2025

Citations

0
Atomic-Scale Observation of Moiré Potential in Twisted Hexagonal Boron Nitride Layers by Electron Microscopy DOI
Ryota Mishima, Takuro Nagai, Hiroyo Segawa

et al.

The Journal of Physical Chemistry C, Journal Year: 2025, Volume and Issue: unknown

Published: April 15, 2025

Language: Английский

Citations

0
Moiré collective vibrations in atomically thin van der Waals superlattices DOI Creative Commons

Lijia Li,

Jiajun Chen, Laigui Hu

et al.

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

Published: May 2, 2025

Collective vibration is pivotal for materials' thermal, electrical, phase transition and topological properties. Lately, the rising of moiré superlattices, characterized by overarching periodicity pattern, generates highly tunable interfacial structures that manipulate collective excitations in material at atomic scale. Here, we experimentally demonstrate vibrations, mechanical counterparts excitons, heterointerfaces twisted tungsten diselenide/tungsten disulfide heterobilayers. Using helicity-resolved inelastic Raman scattering, find chiral phonons carrying angular momentum analogous to bulk quartz, enabling unprecedented spectral resolution rich vibrational modes heterointerface a few layers. Upon mutual torsion heterobilayers, observe terahertz interlayer vibrations proportional as periodic function rotation angles, demonstrating moiré-tuned which couple Coulomb-bound electron-hole pairs excitons. In low-angle strong coupling regime, dynamics exhibit distinct long-lived breathing mode with zero pronounced high energy, highlighting phonon-hybridization character wherein intralayer are folded into mini-Brillouin zone spatial hybridize vibrations. Our findings establish candidates exploitation energy-efficient thermal management, strongly correlated electrical engineering, new emergent phononics.

Language: Английский

Citations

0
Diffusion of Valley-Coherent Dark Excitons in a Large-Angle Incommensurate Moiré Homobilayer DOI Creative Commons
Arnab Barman Ray,

Trevor Ollis,

S. Raju

et al.

Nano Letters, Journal Year: 2025, Volume and Issue: unknown

Published: March 14, 2025

Recent research in twistronics, particularly small-angle twisted bilayers of transition metal dichalcogenides, has uncovered exciting phenomena like periodic arrays excitonic quantum emitters, exotic many-body states, and long-lived interlayer excitons. However, less explored been the physics large-angle, incommensurate bilayers, where periodicity breaks down. In this study, we demonstrate emergence a brightened dark intralayer exciton n-doped molybdenum diselenide homobilayer. This diffuses more efficiently than bright excitons or trions, with diffusion lengths over 4 μm. Temperature-dependent spectra show trion, observe robust valley coherence. unique behavior is attributed to small mixing spin-resolved conduction bands, caused by lack out-of-plane reflection symmetry strong dielectric contrast. Our findings open new possibilities for valleytronic devices using valley-robust "mixed"

Language: Английский

Citations

0