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arXiv · 2502.03590

Topological phases of non-interacting systems: A general approach based on states

Giuseppe De Nittis
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Abstract

In this work we provide a classification scheme for topological phases of certain systems whose observable algebra is described by a trivial $C^*$-bundles. The classification is based on the study of the homotopy classes of \emph{configurations}, which are maps from a \emph{quantum parameter space} to the space of pure states of a reference \emph{fiber} $C^*$-algebra. Both the quantum parameter space and the fiber algebra are naturally associated with the observable algebra. A list of various examples described in the last section shows that the common classification scheme of non-interacting topological insulators of type A is recovered inside this new formalism.

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Giuseppe De Nittis. 2025-02-05. Topological phases of non-interacting systems: A general approach based on states. https://arxiv.org/abs/2502.03590

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