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arXiv · 2106.14769

Measurement of Topological Order based on Metric-Curvature Correspondence

Gero von Gersdorff·Wei Chen
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Abstract

A unified expression for topological invariants has been proposed recently to describe the topological order in Dirac models belonging to any dimension and symmetry class. We uncover a correspondence between the curvature function that integrates to this unified topological invariant and the quantum metric that measures the distance between properly defined many-body Bloch states in momentum space. Based on this metric-curvature correspondence, a time-resolved and angle-resolved photoemission spectroscopy experiment is proposed to measure the violation of spectral sum rule caused by a pulse electric field to detect the quantum metric, from which the topological properties of the system may be extracted.

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Gero von Gersdorff, Wei Chen. 2021-11-18. Measurement of Topological Order based on Metric-Curvature Correspondence. https://doi.org/10.1103/physrevb.104.195133

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