English
Related papers

Related papers: Hopf Insulators and Their Topologically Protected …

200 papers

The Hopf insulators are characterized by a topological invariant called Hopf index which classifies maps from three-sphere to two-sphere, instead of a Chern number or a Chern parity. In contrast to topological insulator, the Hopf insulator…

Mesoscale and Nanoscale Physics · Physics 2015-06-22 Chang-Yan Wang , Yan He

Three-dimensional (3D) two-band Hopf insulators are a paradigmatic example of topological phases beyond the topological classifications based on powerful methods like $K$-theory and symmetry indicators.Since this class of topological…

Mesoscale and Nanoscale Physics · Physics 2023-02-06 Zhu Wang , Xu-Tao Zeng , Yuanchuan Biao , Zhongbo Yan , Rui Yu

Hopf insulators are intriguing three-dimensional topological insulators characterized by an integer topological invariant. They originate from the mathematical theory of Hopf fibration and epitomize the deep connection between knot theory…

The Hopf insulator is a weak topological insulator characterized by an insulating bulk with conducting edge states protected by an integer-valued linking number invariant. The state exists in three-dimensional two-band models. We…

An electron moving in a magnetically ordered background feels an effective magnetic field that can be both stronger and more rapidly varying than typical externally applied fields. One consequence is that insulating magnetic materials in…

Mesoscale and Nanoscale Physics · Physics 2009-11-13 Joel E. Moore , Ying Ran , Xiao-Gang Wen

Hopf insulator is a representative class of three-dimensional topological insulators beyond the standard topological classification methods based on K-theory. In this letter, we discover the metallic counterpart of the Hopf insulator in the…

Mesoscale and Nanoscale Physics · Physics 2025-04-25 Seik Pak , Cheol Hun Yeom , Sonu Verma , Moon Jip Park

Hopf insulators represent a unique class of topological insulators that exist exclusively in two-band systems and are inherently unstable upon the inclusion of additional bands. Meanwhile, recent studies have shown that non-Hermiticity…

Mesoscale and Nanoscale Physics · Physics 2025-08-20 Daichi Nakamura , Kohei Kawabata

Establishing the fundamental relation between the homotopy invariants and the band topology of Hamiltonians has played a critical role in the recent development of topological phase research. In this work, we establish the homotopy…

Mesoscale and Nanoscale Physics · Physics 2023-03-28 Hyeongmuk Lim , Sunje Kim , Bohm-Jung Yang

Topological insulators are electronic materials that have a bulk band gap like an ordinary insulator, but have protected conducting states on their edge or surface. The 2D topological insulator is a quantum spin Hall insulator, which is a…

Mesoscale and Nanoscale Physics · Physics 2015-03-13 M. Z. Hasan , C. L. Kane

Topological insulators are new quantum states with helical gapless edge or surface states inside the bulk band gap.These topological surface states are robust against the weak time-reversal invariant perturbations, such as lattice…

Mesoscale and Nanoscale Physics · Physics 2013-08-07 Haijun Zhang , Shou-Cheng Zhang

Hopf insulators are topological insulators whose topological behavior arises from the nontrivial mapping from a 3D sphere to a 2D sphere, known as the Hopf map. The Hopf map, typically encountered in the study of spinor and skyrmion…

Optics · Physics 2022-10-12 Bo Leng , Vien Van

We discuss a class of three-band non-Abelian topological insulators in three dimensions that carry a single bulk Hopf index protected by spatiotemporal ($\mathcal{PT}$) inversion symmetry. These phases may also host subdimensional…

Mesoscale and Nanoscale Physics · Physics 2024-08-21 Wojciech J. Jankowski , Arthur S. Morris , Zory Davoyan , Adrien Bouhon , F. Nur Ünal , Robert-Jan Slager

We present a quantitative, near-term experimental blueprint for the quantum simulation of topological insulators using lattice-trapped ultracold polar molecules. In particular, we focus on the so-called Hopf insulator, which represents a…

We study a class of $3d$ and $4d$ topological insulators whose topological nature is characterized by the Hopf map and its generalizations. We identify the symmetry $\mathcal{C}^\prime$, a generalized particle-hole symmetry that gives the…

Strongly Correlated Electrons · Physics 2017-05-03 Chunxiao Liu , Farzan Vafa , Cenke Xu

Hopf insulators represent an exceptional class of topological matter unanticipated by the periodic table of topological invariants. These systems point to the existence of previously unexplored states of matter with unconventional topology.…

Strongly Correlated Electrons · Physics 2025-12-19 Konstantinos Ladovrechis , Shouvik Sur

Symmetry Protected Topological (SPT) phases are a minimal generalization of the concept of topological insulators to interacting systems. In this paper we describe the classification and properties of such phases for three dimensional(3D)…

Strongly Correlated Electrons · Physics 2015-06-01 Chong Wang , T. Senthil

Three-dimensional topological (crystalline) insulators are materials with an insulating bulk, but conducting surface states which are topologically protected by time-reversal (or spatial) symmetries. Here, we extend the notion of…

Mesoscale and Nanoscale Physics · Physics 2018-06-05 Frank Schindler , Ashley M. Cook , Maia G. Vergniory , Zhijun Wang , Stuart S. P. Parkin , B. Andrei Bernevig , Titus Neupert

Topological insulators are new class of materials which are characterized by a bulk band gap like ordinary band insulator but have protected conducting states on their edge or surface. These states emerge out due to the combination of…

Mesoscale and Nanoscale Physics · Physics 2017-08-18 Arijit Saha , Arun M. Jayannavar

Three dimensional topological insulator represents a class of novel quantum phases hosting robust gapless boundary excitations, which is protected by global symmetries such as time reversal, charge conservation and spin rotational symmetry.…

Mesoscale and Nanoscale Physics · Physics 2014-03-25 Yuan-Ming Lu , Dung-Hai Lee

We predict the existence of a novel Floquet topological insulator in three-dimensional two-band systems, the Floquet Hopf insulator, which possesses two distinct topological invariants. One is the Hopf $\mathbb{Z}$ invariant, a linking…

Mesoscale and Nanoscale Physics · Physics 2020-01-08 Thomas Schuster , Snir Gazit , Joel E. Moore , Norman Y. Yao
‹ Prev 1 2 3 10 Next ›