English
Related papers

Related papers: A Brillouin torus decomposition for two-dimensiona…

200 papers

We apply methods of equivariant homotopy theory, which may not previously have found due attention in condensed matter physics, to classify first the fragile/unstable topological phases of 2D crystalline Chern insulator materials, and…

Strongly Correlated Electrons · Physics 2026-01-01 Hisham Sati , Urs Schreiber

Here we study the systematic evolution of the topological properties of a Chern insulator in presence of an electronic dispersion that can be tuned smoothly from being Dirac-like till a semi-Dirac one and beyond. The band structure under…

Mesoscale and Nanoscale Physics · Physics 2022-03-31 Sayan Mondal , Priyadarshini Kapri , Bashab Dey , Tarun Kanti Ghosh , Saurabh Basu

The Chern number is a crucial topological invariant for distinguishing the phases of Chern insulators. Here we find that for Chern insulators with inversion symmetry, the Chern number alone is insufficient to fully characterize their…

Mesoscale and Nanoscale Physics · Physics 2024-10-01 Yu-Hao Wan , Peng-Yi Liu , Qing-Feng Sun

We develop a technique for constructing Bloch-like functions for 2D Z_2-insulators (i.e., quantum spin-Hall insulators) that are smooth functions of k on the entire Brillouin-zone torus. As the initial step, the occupied subspace of the…

Mesoscale and Nanoscale Physics · Physics 2012-03-19 Alexey A. Soluyanov , David Vanderbilt

Unlike broken time-reversal symmetric (TRS) systems with a defined Chern number, directly measuring the bulk $Z_{2}$ invariant and Berry curvature (if nonzero) in topological insulators and their higher-order topological families remains an…

Mesoscale and Nanoscale Physics · Physics 2026-01-12 Pok Man Chiu

The topological structure of the wavefunctions of particles in periodic potentials is characterized by the Berry curvature $\Omega_{kn}$ whose integral on the Brillouin zone is a topological invariant known as the Chern number. The…

Mesoscale and Nanoscale Physics · Physics 2016-11-21 Lucila Peralta Gavensky , Gonzalo Usaj , C. A. Balseiro

Ideal Chern insulating phases arise in two-dimensional systems with broken time-reversal symmetry. They are characterized by having nearly-flat bands, and a uniform quantum geometry -- which combines the Berry curvature and quantum metric…

Mesoscale and Nanoscale Physics · Physics 2022-04-18 Christian Northe , Giandomenico Palumbo , Jonathan Sturm , Christian Tutschku , Ewelina M. Hankiewicz

We describe a systematic method to construct models of Chern insulators whose Berry curvature and the quantum volume form coincide and are flat over the Brillouin zone; such models are known to be suitable for hosting fractional Chern…

Mesoscale and Nanoscale Physics · Physics 2021-09-28 Bruno Mera , Tomoki Ozawa

The Berry curvature in Chern insulators appears to be a non-gauge-invariant quantity and does not immediately allow local length characterization. However, in two examples of 2- and 3-band models that we discuss, we find high-symmetry…

Mesoscale and Nanoscale Physics · Physics 2014-06-25 E. Dobardžić , M. Dimitrijević , M. V. Milovanović

The topology of electronic states in band insulators with mirror symmetry can be classified in two different ways. One is in terms of the mirror Chern number, an integer that counts the number of protected Dirac cones in the Brillouin zone…

Mesoscale and Nanoscale Physics · Physics 2021-05-10 Tomáš Rauch , Thomas Olsen , David Vanderbilt , Ivo Souza

Band geometry plays a substantial role in topological lattice models. The Berry curvature, which resembles the effect of magnetic field in reciprocal space, usually fluctuates throughout the Brillouin zone. Motivated by the analogy with…

Strongly Correlated Electrons · Physics 2022-04-11 Daniel Varjas , Ahmed Abouelkomsan , Kang Yang , Emil J. Bergholtz

We study the ground-state topology and quasiparticle properties in bosonic Mott insulators with two- dimensional spin-orbit couplings in cold atomic optical lattices. We show that the many-body Chern and spin-Chern number can be expressed…

Mesoscale and Nanoscale Physics · Physics 2013-12-04 Clement H. Wong , R. A. Duine

We study the topological gap labeling of general 3D quasicrystals and we find that every gap in the spectrum is characterized by a set of the third Chern numbers. We show that a quasi-periodic structure has multiple Brillouin zones defined…

Mesoscale and Nanoscale Physics · Physics 2022-03-23 Kazuki Yamamoto , Mikito Koshino

We investigate the quantum metric and topological Euler number in a cyclically modulated Su-Schrieffer-Heeger (SSH) model with long-range hopping terms. By computing the quantum geometry tensor, we derive exactly expressions for the quantum…

Strongly Correlated Electrons · Physics 2024-04-15 Xiang-Long Zeng , Wen-Xi Lai , Yi-Wen Wei , Yu-Quan Ma

We propose to use generic Chern numbers for a characterization of topological insulators. It is suitable for a numerical characterization of low dimensional quantum liquids where strong quantum fluctuations prevent from developing…

Strongly Correlated Electrons · Physics 2009-11-10 Yasuhiro Hatsugai

Despite sharing a common lattice structure, monolayer M$_2$X$_2$ compounds realize quantum anomalous Hall phases with distinct Chern numbers, a striking phenomenon that has not been fully exploared. Combining first-principles calculations…

Materials Science · Physics 2025-09-09 Zujian Dai , Xudong Zhu , Lixin He

Quantum metrology is deeply connected to quantum geometry, through the fundamental notion of quantum Fisher information. Inspired by advances in topological matter, it was recently suggested that the Berry curvature and Chern numbers of…

Quantum Physics · Physics 2024-11-12 Min Yu , Xiangbei Li , Yaoming Chu , Bruno Mera , F. Nur Ünal , Pengcheng Yang , Yu Liu , Nathan Goldman , Jianming Cai

The appearance of fractional Chern insulators in moir\'e systems can be rationalized by the presence of a fictitious magnetic field associated with the spatial texture of layer-resolved electronic wavefunctions. Here, we present a…

Mesoscale and Nanoscale Physics · Physics 2025-07-02 Kryštof Kolář , Kang Yang , Felix von Oppen , Christophe Mora

We study the entanglement spectrum of noninteracting band insulators, which can be computed from the two-point correlation function, when restricted to one part of the system. In particular, we analyze a type of partitioning of the system…

Strongly Correlated Electrons · Physics 2013-09-18 Markus Legner , Titus Neupert

In this paper, we formulate the real-space Chern number in a supercell framework. In this framework, the overlap matrix between two corners of the Brillouin zone (BZ) is derived from diagonalizing the real-space Hamiltonian with periodic…

Mesoscale and Nanoscale Physics · Physics 2026-04-15 Kiminori Hattori , Shinji Nakata