# Magic-angle semimetals

@article{Fu2018MagicangleS, title={Magic-angle semimetals}, author={Yixing Fu and Elio J. K{\"o}nig and Justin H. Wilson and Yang-Zhi Chou and Jedediah H. Pixley}, journal={npj Quantum Materials}, year={2018}, volume={5}, pages={1-8} }

Breakthroughs in two-dimensional van der Waals heterostructures have revealed that twisting creates a moiré pattern that quenches the kinetic energy of electrons, allowing for exotic many-body states. We show that cold atomic, trapped ion, and metamaterial systems can emulate the effects of a twist in many models from one to three dimensions. Further, we demonstrate at larger angles (and argue at smaller angles) that by considering incommensurate effects, the magic-angle effect becomes a single…

## 25 Citations

Moiré superlattice on the surface of a topological insulator

- Physics
- 2020

Twisting van der Waals heterostructures to induce correlated many-body states provides a novel tuning mechanism in solid-state physics. In this work, we theoretically investigate the fate of the…

The low energy excitation spectrum of magic-angle semimetals

- Physics
- 2022

We theoretically study the excitation spectrum of a two-dimensional Dirac semimetal in the presence of an incommensurate potential. Such models have been shown to possess magic-angle critical points…

Emulating twisted double bilayer graphene with a multiorbital optical lattice

- Physics
- 2021

This work theoretically explores how to emulate twisted double bilayer graphene with ultracold atoms in multiorbital optical lattices. In particular, the quadratic band touching of Bernal stacked…

Extremely flat band in antiferroelectric bilayer α-In2Se3 with large twist-angle

- Physics
- 2021

The moiré-pattern with slightly interlayer-twisted bilayer two-dimensional (2D) materials has recently been receiving substantial attention. One of the major characters for these intriguing…

Rare regions and avoided quantum criticality in disordered Weyl semimetals and superconductors

- PhysicsAnnals of Physics
- 2021

Superfluidity and Quantum Geometry in Twisted Multilayer Systems

- Physics
- 2021

Designer 2D materials where the constituent layers are not aligned may result in band structures with dispersionless, “flat” bands. Twisted bilayer graphene has been found to show correlated phases…

Magic angles and current-induced topology in twisted nodal superconductors

- Physics
- 2020

Motivated by the recent achievements in the realization of strongly correlated and topological phases in twisted van der Waals heterostructures, we study the low-energy properties of a twisted…

Josephson effects in twisted nodal superconductors

- Physics
- 2021

Motivated by the recent proposals for unconventional emergent physics in twisted bilayers of nodal superconductors, we study the peculiarities of the Josephson effect at the twisted interface between…

TBG II: Stable Symmetry Anomaly in Twisted Bilayer Graphene

- Physics
- 2020

We show that the entire continuous model of twisted bilayer graphene (TBG) (and not just the two active bands) with particle-hole symmetry is anomalous and hence incompatible with a lattice model.…

TBG I: Matrix Elements, Approximations, Perturbation Theory and a $k\cdot p$ 2-Band Model for Twisted Bilayer Graphene

- Physics
- 2020

We investigate the Twisted Bilayer Graphene (TBG) model to obtain an analytic understanding of its energetics and wavefunctions needed for many-body calculations. We provide an approximation scheme…

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