Semiconductor moiré materials

Nature Nanotechnology, Journal Year: 2022, Volume and Issue: 17(7), P. 686 - 695

Published: July 1, 2022

Language: Английский

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Thermodynamic evidence of fractional Chern insulator in moiré MoTe2

Nature, Journal Year: 2023, Volume and Issue: 622(7981), P. 69 - 73

Published: July 26, 2023

Language: Английский

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Anomalous Hall metal and fractional Chern insulator in twisted transition metal dichalcogenides

Physical review. B./Physical review. B, Journal Year: 2023, Volume and Issue: 107(20)

Published: May 10, 2023

We predict robust Ising ferromagnetism driven by Coulomb interaction in the metallic phase of twisted transition metal dichalcogenide homobilayers for a range small twist angles. Due to presence spin-valley locking and Chern band, completely spin-polarized state---a half metal---has spin gap exhibits anomalous Hall effect. also find that near magic angle where band is predicted be exceptionally flat, at $1/3$ filling may become unstable low temperature change into $\sqrt{3}\ifmmode\times\else\texttimes\fi{}\sqrt{3}$ charge density wave or fractional insulator.

Language: Английский

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Programming correlated magnetic states with gate-controlled moiré geometry

Science, Journal Year: 2023, Volume and Issue: 381(6655), P. 325 - 330

Published: June 22, 2023

The ability to control the underlying lattice geometry of a system may enable transitions between emergent quantum ground states. We report in situ gate switching honeycomb and triangular geometries an electron many-body Hamiltonian rhombohedral (R)-stacked molybdenum ditelluride (MoTe2) moiré bilayers, resulting switchable magnetic exchange interactions. At zero electric field, we observed correlated ferromagnetic insulator near one hole per unit cell with widely tunable Curie temperature up 14 K. Applying field switched into half-filled antiferromagnetic interactions; further doping this layer-polarized superlattice tuned interaction back ferromagnetic. Our work demonstrates R-stacked MoTe2 moirés be laboratory for engineering states nontrivial topology.

Language: Английский

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Substrate engineering for wafer-scale two-dimensional material growth: strategies, mechanisms, and perspectives

Chemical Society Reviews, Journal Year: 2023, Volume and Issue: 52(5), P. 1650 - 1671

Published: Jan. 1, 2023

This review focuses on the existing strategies and underlying mechanisms, discusses future directions in epitaxial substrate engineering to deliver wafer-scale 2D materials for integrated electronics photonics.

Language: Английский

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Evidence of the fractional quantum spin Hall effect in moiré MoTe2

Nature, Journal Year: 2024, Volume and Issue: 628(8008), P. 522 - 526

Published: March 20, 2024

Language: Английский

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Composite Fermi Liquid at Zero Magnetic Field in Twisted MoTe2

Physical Review Letters, Journal Year: 2023, Volume and Issue: 131(13)

Published: Sept. 27, 2023

The pursuit of exotic phases matter outside the extreme conditions a quantizing magnetic field is long-standing quest solid state physics. Recent experiments have observed spontaneous valley polarization and fractional Chern insulators in zero twisted bilayers MoTe2, at partial filling topological valence band (ν=−2/3 −3/5). We study half filling, using exact diagonalization density matrix renormalization group calculations. discover composite Fermi liquid (CFL) phase even that covers large portion diagram near twist angle ∼3.6°. CFL non-Fermi with metallic behavior despite absence Landau quasiparticles. discuss experimental implications including competition between liquid, which can be tuned displacement field. has excellent quantum geometry over wide range angles small bandwidth is, remarkably, reduced by interactions. These key properties stabilize Hall phases. Finally, we present an optical signature involving "extinguished" responses detects bands ideal geometry.Received 14 June 2023Accepted 25 August 2023DOI:https://doi.org/10.1103/PhysRevLett.131.136502© 2023 American Physical SocietyPhysics Subject Headings (PhySH)Research AreasComposite fermionsFermi surfaceFlat bandsLandau levelsOptical conductivityTopological materialsTopological matterTwistronicsPhysical SystemsTransition metal dichalcogenidesTwisted heterostructuresTechniquesBand structure methodsDensity methodsExact diagonalizationHartree-Fock methodsCondensed Matter, Materials & Applied Physics

Language: Английский

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Phase Engineering of 2D Materials

Chemical Reviews, Journal Year: 2023, Volume and Issue: 123(19), P. 11230 - 11268

Published: Aug. 17, 2023

Polymorphic 2D materials allow structural and electronic phase engineering, which can be used to realize energy-efficient, cost-effective, scalable device applications. The engineering covers not only conventional metal–insulator transitions but also magnetic states, strongly correlated band structures, topological phases in rich materials. methods for the local of include various optical, geometrical, chemical processes as well traditional thermodynamic approaches. In this Review, we survey precise manipulation patterning materials, particularly with ideal versatile interfaces energy diverse quantum their layered, vertical, lateral geometries are discussed an emphasis on role use interfaces. Various have demonstrated superior unique performance devices. leads novel homo- heterojunction structures low-dimensional boundaries, highlights potential technological breakthroughs future electronic, quantum, Accordingly, encourage researchers investigate exploit emerging

Language: Английский

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Mapping twist-tuned multiband topology in bilayer WSe ₂

Science, Journal Year: 2024, Volume and Issue: 384(6693), P. 343 - 347

Published: April 18, 2024

Semiconductor moiré superlattices have been shown to host a wide array of interaction-driven ground states. However, twisted homobilayers difficult study in the limit large wavelengths, where interactions are most dominant. In this study, we conducted local electronic compressibility measurements bilayer WSe

Language: Английский

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Moiré fractional Chern insulators. I. First-principles calculations and continuum models of twisted bilayer MoTe2

Physical review. B./Physical review. B, Journal Year: 2024, Volume and Issue: 109(20)

Published: May 7, 2024

The researchers here shed new light on the elusive single-particle model of twisted bilayer MoTe${}_{2}$, a material recently highlighted for hosting fractional Chern insulators at zero magnetic field. By leveraging an advanced machine learning method and density functional theory, team meticulously maps out band structure across various twist angles, revealing pivotal inversion refining theoretical landscape. enhancing continuum with higher harmonic terms, they unveil opposite numbers in valence bands key paving way predicting diverse states. This comprehensive analysis lays groundwork accurately pinpointing correlated phases this intriguing material, offering beacon future explorations.

Language: Английский

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