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arXiv · 2010.14466

A Constructive Approach to Topological Invariants for One-dimensional Strictly Local Operators

Yohei Tanaka
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Abstract

In this paper we shall focus on one-dimensional strictly local operators, the notion of which naturally arises in the context of discrete-time quantum walks on the one-dimensional integer lattice. In particular, we give an elementary constructive approach to the following two topological invariants associated with such operators: Fredholm index and essential spectrum. As a direct application, we shall explicitly compute and fully classify these topological invariants for a well-known quantum walk model.

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Yohei Tanaka. 2020-10-27. A Constructive Approach to Topological Invariants for One-dimensional Strictly Local Operators. https://doi.org/10.1016/j.jmaa.2021.125072

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