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arXiv · 2608.27767

Fractional Hall Conductance of Laughlin States from a Topological Index

Sven Bachmann·Severin Schraven·Jacob Shapiro·Simone Warzel
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Abstract

We provide a rigorous Laughlin-pump argument that establishes the fractional quantization of the Hall conductance directly from the Laughlin state as a topological index. Our proof uses a recently defined index of a pair of pure states together with an infinite matrix product state analysis that is rigorous on a sufficiently thin cylinder. By virtue of the connection to an index, our result implies, in particular, that Laughlin states are representatives of topologically stable fractional quantum Hall phases.

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Sven Bachmann, Severin Schraven, Jacob Shapiro, Simone Warzel. 2026-08-27. Fractional Hall Conductance of Laughlin States from a Topological Index. https://arxiv.org/abs/2608.27767

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