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arXiv · 2508.08239

Readout of multi-level quantum geometry from electronic transport

Raffael L. Klees·Mónica Benito
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Abstract

The quantum geometric tensor (QGT) of a quantum system in a given parameter space captures both the geometry of the state manifold and the topology of the system. While the local QGT elements have been successfully measured in various platforms, the challenge of detecting them in electronic transport systems - such as tunnel or molecular junctions - has yet to be resolved. To fill this gap, we propose a measurement protocol based on weak and resonant parameter modulations, and theoretically demonstrate how the local QGT in such systems can be directly probed from changes of the tunnel conductance. This approach enables the measurement of both geometrical and topological features of quantum states in a broad class of transport-based quantum systems.

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Raffael L. Klees, Mónica Benito. 2025-08-11. Readout of multi-level quantum geometry from electronic transport. https://arxiv.org/abs/2508.08239

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