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Related papers: Imaging orbital ferromagnetism in a moir\'e Chern …

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Within a relativistic quantum formalism we examine the role of second-order corrections caused by the application of magnetic fields in two-dimensional topological and Chern insulators. This allows to reach analytical expressions for the…

Mesoscale and Nanoscale Physics · Physics 2021-11-01 Daniel Faílde , Daniel Baldomir

The symmetry considerations that imply a non-zero anomalous Hall effect (AHE) in certain non-collinear antiferromagnets also imply both non-zero orbital magnetization and a net spin magnetization. We have explicitly evaluated the orbital…

Mesoscale and Nanoscale Physics · Physics 2020-04-01 Hua Chen , Tzu-Cheng Wang , Di Xiao , Guang-Yu Guo , Qian Niu , Allan H. MacDonald

We show that interacting electrons in a flat Chern band can form, in addition to fractional Chern insulators, a chiral $f$-wave topological superconductor that hosts neutral Majorana fermion edge modes. Superconductivity emerges from an…

Superconductivity · Physics 2025-10-23 Daniele Guerci , Ahmed Abouelkomsan , Liang Fu

Asymmetric magnetization reversal is an unusual phenomenon in antiferromagnet / ferromagnet (AF/FM) exchange biased bilayers. We investigated this phenomenon in a simple model system experimentally and by simulation assuming inhomogeneously…

Materials Science · Physics 2009-11-11 Zhi-Pan Li , Oleg Petracic , Rafael Morales , Justin Olamit , Xavier Batlle , Kai Liu , Ivan K. Schuller

We predict the emergence a state of matter with intertwined ferromagnetism, charge order and topology in fractionally filled moir\'e superlattice bands. Remarkably, these quantum anomalous Hall crystals exhibit a quantized integer Hall…

Mesoscale and Nanoscale Physics · Physics 2024-08-20 D. N. Sheng , Aidan P. Reddy , Ahmed Abouelkomsan , Emil J. Bergholtz , Liang Fu

We study an effective low-energy Kondo model on the triangular lattice in which itinerant electrons occupy a valence pocket at $\Gamma$ and three conduction pockets at the $M$ points of the Brillouin zone. This construction has a…

Strongly Correlated Electrons · Physics 2026-04-21 Kai Vylet , Xingkai Huang , Leon Balents

The anomalous Hall effect, observed in conducting ferromagnets with broken time-reversal symmetry, offers the possibility to couple spin and orbital degrees of freedom of electrons in ferromagnets. In addition to charge, the anomalous Hall…

Materials Science · Physics 2018-07-04 Yumeng Yang , Ziyan Luo , Haijun Wu , Yanjun Xu , Run-Wei Li , Stephen J. Pennycook , Shufeng Zhang , Yihong Wu

We propose a magnon-driven anomalous Hall effect in altermagnets, arising from the coupling between coherently excited chiral magnons and chiral electronic motion. Using density-matrix perturbation theory and symmetry analysis, we show that…

Mesoscale and Nanoscale Physics · Physics 2026-03-23 Zheng Liu , Yang Gao , Qian Niu

At partial filling of a flat band, strong electronic interactions may favor gapped states harboring emergent topology with quantized Hall conductivity. Emergent topological states have been found in partially filled Landau levels and…

We report a nearly ideal quantum anomalous Hall effect in a three-dimensional topological insulator thin film with ferromagnetic doping. Near zero applied magnetic field we measure exact quantization in Hall resistance to within a part per…

Mesoscale and Nanoscale Physics · Physics 2015-05-13 A. J. Bestwick , E. J. Fox , Xufeng Kou , Lei Pan , Kang L. Wang , D. Goldhaber-Gordon

Progress in magnetoelectric materials is hindered by apparently contradictory requirements for time-reversal symmetry broken and polar ferroelectric electronic structure in common ferromagnets and antiferromagnets. Alternative routes could…

Reading antiferromagnetic order remains a central obstacle for antiferromagnetic memory and logic because zero net magnetisation precludes conventional magnetic readout. Domain imaging typically relies on x-ray magnetic linear dichroism…

We show that the quantum anomalous Hall effect almost always occurs in magnetic topological insulator thin films whenever the top and bottom surface layer magnetizations are parallel, independent of the interior layer magnetization…

Mesoscale and Nanoscale Physics · Physics 2022-12-07 Chao Lei , Olle Heinonen , R. J. McQueeney , A. H. MacDonald

We derive a multi-band formulation of the orbital magnetization in a normal periodic insulator (i.e., one in which the Chern invariant, or in 2d the Chern number, vanishes). Following the approach used recently to develop the single-band…

Materials Science · Physics 2009-11-11 Davide Ceresoli , T. Thonhauser , David Vanderbilt , R. Resta

The understanding of the Chern insulator and anomalous quantum Hall effect (AQHE) in terms of chiral edge states in confined systems is the first aim of the paper. The model we use consists in a diatomic square lattice with hopping to the…

Mesoscale and Nanoscale Physics · Physics 2018-09-12 B. Ostahie , M. Nita , A. Aldea

Flat bands in graphene-based moir\'e structures host a wide range of emerging strongly correlated and topological phenomena. Optically probing and controlling them can reveal important information such as symmetry and dynamics, but have so…

Strongly Correlated Electrons · Physics 2025-03-28 Eylon Persky , Minhao He , Jiaqi Cai , Takashi Taniguchi , Kenji Watanabe , Xiaodong Xu , Aharon Kapitulnik

The nodal points in a Weyl semimetal are generally considered as the causes of the chiral anomaly and the chiral magnetic effect (CME). Employing a linear-response analysis of a two-band lattice model, we show that the Weyl nodes and thus…

Mesoscale and Nanoscale Physics · Physics 2015-11-10 Ming-Che Chang , Min-Fong Yang

Quantum anomalous Hall effect, with a trademark of dissipationless chiral edge states for electronics/spintronics transport applications, can be realized in materials with large spin-orbit coupling and strong intrinsic magnetization. After…

Mesoscale and Nanoscale Physics · Physics 2021-01-05 Muhammad Nadeem , Alex R. Hamilton , Michael S. Fuhrer , Xiaolin Wang

Recently Chern insulators with Chern number $C=1$ and $C=2$ in zero (or very small) magnetic field have been observed in two moire graphene systems: twisted bilayer graphene and ABC trilayer graphene, both aligned with a hexagonal…

Strongly Correlated Electrons · Physics 2020-10-07 Ya-Hui Zhang , T. Senthil

We study the behaviour of electrons interacting with a classical magnetic background via a strong Hund coupling. The magnetic background results from a Hamiltonian which favours at low temperature the emergence of a phase with non-zero…

Strongly Correlated Electrons · Physics 2019-02-06 H. D. Rosales , F. A. Gómez Albarracín , P. Pujol