A non-commutative framework for topological insulators
We study topological insulators, regarded as physical systems giving rise to topological
invariants determined by symmetries both linear and anti-linear. Our perspective is that of …
invariants determined by symmetries both linear and anti-linear. Our perspective is that of …
Wannier functions and invariants in time-reversal symmetric topological insulators
We provide a constructive proof of exponentially localized Wannier functions and related
Bloch frames in 1-and 2-dimensional time-reversal symmetric (TRS) topological insulators …
Bloch frames in 1-and 2-dimensional time-reversal symmetric (TRS) topological insulators …
The K-Theoretic Bulk–Edge Correspondence for Topological Insulators
We study the application of Kasparov theory to topological insulator systems and the bulk–
edge correspondence. We consider observable algebras as modelled by crossed products …
edge correspondence. We consider observable algebras as modelled by crossed products …
The topological classification of one-dimensional symmetric quantum walks
C Cedzich, T Geib, FA Grünbaum, C Stahl… - Annales Henri …, 2018 - Springer
We give a topological classification of quantum walks on an infinite 1D lattice, which obey
one of the discrete symmetry groups of the tenfold way, have a gap around some …
one of the discrete symmetry groups of the tenfold way, have a gap around some …
Index pairings in presence of symmetries with applications to topological insulators
J Großmann, H Schulz-Baldes - Communications in Mathematical Physics, 2016 - Springer
In a basic framework of a complex Hilbert space equipped with a complex conjugation and
an involution, linear operators can be real, quaternionic, symmetric or anti-symmetric, and …
an involution, linear operators can be real, quaternionic, symmetric or anti-symmetric, and …
The noncommutative index theorem and the periodic table for disordered topological insulators and superconductors
H Katsura, T Koma - Journal of Mathematical Physics, 2018 - pubs.aip.org
We study a wide class of topological free-fermion systems on a hypercubic lattice in spatial
dimensions d≥ 1. When the Fermi level lies in a spectral gap or a mobility gap, the …
dimensions d≥ 1. When the Fermi level lies in a spectral gap or a mobility gap, the …
Complete homotopy invariants for translation invariant symmetric quantum walks on a chain
C Cedzich, T Geib, C Stahl, L Velázquez… - Quantum, 2018 - quantum-journal.org
We provide a classification of translation invariant one-dimensional quantum walks with
respect to continuous deformations preserving unitarity, locality, translation invariance, a …
respect to continuous deformations preserving unitarity, locality, translation invariance, a …
Skew localizer and Z2-flows for real index pairings
N Doll, H Schulz-Baldes - Advances in Mathematics, 2021 - Elsevier
Real index pairings of projections and unitaries on a separable Hilbert space with a real
structure are defined when the projections and unitaries fulfill symmetry relations invoking …
structure are defined when the projections and unitaries fulfill symmetry relations invoking …
The ℤ2 index of disordered topological insulators with time reversal symmetry
H Katsura, T Koma - Journal of Mathematical Physics, 2016 - pubs.aip.org
We study disordered topological insulators with time reversal symmetry. Relying on the
noncommutative index theorem which relates the Chern number to the projection onto the …
noncommutative index theorem which relates the Chern number to the projection onto the …
Chern numbers, localisation and the bulk-edge correspondence for continuous models of topological phases
In order to study continuous models of disordered topological phases, we construct an
unbounded Kasparov module and a semifinite spectral triple for the crossed product of a …
unbounded Kasparov module and a semifinite spectral triple for the crossed product of a …