6 papers · 1 filter
The role of self-adjoint extensions in the bulk-edge correspondence
Johannes Kellendonk, Tom Stoiber
We investigate the role of self-adjoint extensions in the bulk-edge correspondence for topological insulators. While the correspondence is well understood in discrete models with s…
On Frustration-Free Quantum Spin Models
Danilo Polo Ojito, Emil Prodan, Tom Stoiber
The goal of our work is to characterize the landscape of the frustration-free quantum spin models over the Cayley graph of a finitely generated group . This is achieved by estab…
Invariant measures on the transversal hull of cone semigroups and some applications
Danilo Polo Ojito, Emil Prodan, Tom Stoiber
Let $\LL_{\bf v}\subset \Z^D$ be a suitable cone semigroup and $\A_{\bf v}$ its reduced semigroup -algebra. In this paper, we compute the $\LL_{\bf v}$-invariant measures in t…
C*-framework for higher-order bulk-boundary correspondences
Danilo Polo Ojito, Emil Prodan, Tom Stoiber
A typical crystal is a finite piece of a material which may be invariant under some point symmetry group. If it is a so-called intrinsic higher-order topological insulator or super…
A space-adiabatic approach for bulk-defect correspondences in lattice models of topological insulators
Danilo Polo Ojito, Emil Prodan, Tom Stoiber
In space-adiabatic approaches one can approximate Hamiltonians that are modulated slowly in space by phase-space functions that depend on position and momentum. In this paper, we e…
A spectral localizer approach to strong topological invariants in the mobility gap regime
Tom Stoiber
Topological phases of gapped one-particle Hamiltonians with (anti)-unitary symmetries are classified by strong topological invariants according to the Altland-Zirnbauer table. Thos…