Testing the Renormalization of the von Klitzing Constant by Cavity Vacuum Fields

Josefine Enkner; Lorenzo Graziotto; Felice Appugliese; Vasil Rokaj; Jie Wang; Michael Ruggenthaler; Christian Reichl; Werner Wegscheider; Angel Rubio; Jérôme Faist

arXiv · 2311.10462

Testing the Renormalization of the von Klitzing Constant by Cavity Vacuum Fields

Josefine Enkner·Lorenzo Graziotto·Felice Appugliese·Vasil Rokaj·Jie Wang·Michael Ruggenthaler·Christian Reichl·Werner Wegscheider·Angel Rubio·Jérôme Faist

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Abstract

In light of recent developments demonstrating the impact of cavity vacuum fields inducing the breakdown of topological protection in the integer quantum Hall effect, a compelling question arises: what effects might cavity vacuum fields have on fundamental constants in solid-state systems? In this work we present an experiment that assesses the possibility of the von Klitzing constant itself being modified. By employing a Wheatstone bridge, we precisely measure the difference between the quantized Hall resistance of a cavity-embedded Hall bar and the resistance standard, achieving an accuracy down to 1 part in 105 for the lowest Landau level. While our results do not suggest any deviation that could imply a modified Hall resistance, our work represents pioneering efforts in exploring the fundamental implications of vacuum fields in solid-state systems.

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Josefine Enkner, Lorenzo Graziotto, Felice Appugliese, Vasil Rokaj, Jie Wang, Michael Ruggenthaler, Christian Reichl, Werner Wegscheider, Angel Rubio, Jérôme Faist. 2023-11-17. Testing the Renormalization of the von Klitzing Constant by Cavity Vacuum Fields. https://arxiv.org/abs/2311.10462

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