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Related papers: Topological Insulators and C^*-Algebras: Theory an…

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We complete a classification of topological phases and their topological defects in crystalline insulators and superconductors. We consider topological phases and defects described by non-interacting Bloch and Bogoliubov de Gennes…

Mesoscale and Nanoscale Physics · Physics 2014-10-15 Ken Shiozaki , Masatoshi Sato

In this Letter we supervisedly train neural networks to distinguish different topological phases in the context of topological band insulators. After training with Hamiltonians of one-dimensional insulators with chiral symmetry, the neural…

Mesoscale and Nanoscale Physics · Physics 2018-05-31 Pengfei Zhang , Huitao Shen , Hui Zhai

Topological invariants are global properties of the ground-state wave function, typically defined as winding numbers in reciprocal space. Over the years, a number of topological markers in real space have been introduced, allowing to map…

Mesoscale and Nanoscale Physics · Physics 2024-01-17 Nicolas Baù , Antimo Marrazzo

The study of topological band insulators has revealed fascinating phases characterized by band topology indices and anomalous boundary modes protected by global symmetries. In strongly correlated systems, where the traditional notion of…

Strongly Correlated Electrons · Physics 2025-06-12 Chao Xu , Yixin Ma , Shenghan Jiang

Topological insulators are solid state systems of independent electrons for which the Fermi level lies in a mobility gap, but the Fermi projection is nevertheless topologically non-trivial, namely it cannot be deformed into that of a normal…

Mathematical Physics · Physics 2016-10-27 Hermann Schulz-Baldes

For a large class of physically relevant operators on a manifold with discrete group action, we prove general results on the (non-)existence of a basis of smooth well-localised Wannier functions for their spectral subspaces. This turns out…

Mathematical Physics · Physics 2022-01-19 Matthias Ludewig , Guo Chuan Thiang

A tiling with infinite rotational symmetry, such as the Conway-Radin Pinwheel Tiling, gives rise to a topological dynamical system to which an \'etale equivalence relation is associated. A groupoid C*-algebra for a tiling is produced and a…

Operator Algebras · Mathematics 2010-10-12 Michael F. Whittaker

This paper proposes a quantitative description of the low energy edge states at the interface between two-dimensional topological insulators. They are modeled by continuous Hamiltonians as systems of Dirac equations that are amenable to a…

Mathematical Physics · Physics 2018-08-16 Guillaume Bal

We classify insulators by generalized symmetries that combine space-time transformations with quasimomentum translations. Our group-cohomological classification generalizes the nonsymmorphic space groups, which extend point groups by…

Mesoscale and Nanoscale Physics · Physics 2016-04-18 A. Alexandradinata , Zhijun Wang , B. Andrei Bernevig

The topology of insulators is usually revealed through the presence of gapless boundary modes: this is the so-called bulk-boundary correspondence. However, the many-body wavefunction of a crystalline insulator is endowed with additional…

Mesoscale and Nanoscale Physics · Physics 2021-01-08 Sander H. Kooi , Guido van Miert , Carmine Ortix

A noncommutative space-time admitting dilation symmetry was briefly mentioned in the seminal work of Doplicher, Fredenhagen and Roberts. In this paper we explicitly construct the model in details and carry out an in-depth analysis. The…

General Relativity and Quantum Cosmology · Physics 2015-10-06 Claudio Perini , Gabriele Nunzio Tornetta

Strong invariants of even-dimensional topological insulators of independent Fermions are expressed in terms of an invertible operator on the Hilbert space over the boundary. It is given by the Cayley transform of the boundary restriction of…

Mathematical Physics · Physics 2021-01-25 Hermann Schulz-Baldes , Daniele Toniolo

We provide an index-theoretic proof of the bulk-boundary correspondence for two- and three-dimensional second-order topological insulators that preserve inversion symmetry, which are modeled as rectangles and rectangular prism-shaped…

K-Theory and Homology · Mathematics 2025-09-12 Shin Hayashi

Topological quivers are generalizations of directed graphs in which the sets of vertices and edges are locally compact Hausdorff spaces. Associated to such a topological quiver Q is a C*-correspondence, and from this correspondence one may…

Operator Algebras · Mathematics 2007-05-23 Paul S. Muhly , Mark Tomforde

We study various topological invariants on a torsional geometry in the presence of a totally anti-symmetric torsion H under the closed condition dH = 0, which appears in string theory compactification scenarios. By using the identification…

High Energy Physics - Theory · Physics 2008-11-26 Tetsuji Kimura

We define a categorical framework in which we build a systematic construction that provides generic invariants for C*-algebras. The benefit is significant as we show that any invariant arising this way automatically enjoys nice properties…

Operator Algebras · Mathematics 2023-09-06 Laurent Cantier

We investigate conditions on a graph $C^*$-algebra for the existence of a faithful semifinite trace. Using such a trace and the natural gauge action of the circle on the graph algebra, we construct a smooth $(1,\infty)$-summable semfinite…

Functional Analysis · Mathematics 2007-05-23 David Pask , Adam Rennie

Protected by the chiral symmetry, three dimensional chiral topological insulators are characterized by an integer-valued topological invariant. How this invariant could emerge in physical observables is an important question. Here we show…

Mesoscale and Nanoscale Physics · Physics 2015-01-08 Sheng-Tao Wang , Dong-Ling Deng , Joel E. Moore , Kai Sun , Lu-Ming Duan

The winding number has been widely used as an invariant for diagnosing topological phases in one-dimensional chiral-symmetric systems. We put forward a real-space representation for the winding number. Remarkably, our method reproduces an…

Strongly Correlated Electrons · Physics 2021-06-30 Ling Lin , Yongguan Ke , Chaohong Lee

The standard representation of c*-algebra is used to describe fields in compactified space-time dimensions characterized by topologies of the type $ \Gamma_{D}^{d}=(\mathbb{S}^{1})^{d}\times \mathbb{M}^{D-d}$. The modular operator is…

High Energy Physics - Theory · Physics 2011-07-29 F. C. Khanna , A. P. C. Malbouisson , J. M. C. Malbouisson , A. E. Santana