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arXiv · 2304.03028

Hall anomaly and vortex charge in Bi$_2$Sr$_2$CaCu$_2$O$_x$

Yuval Nitzav·Amit Kanigel
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Abstract

We present a systematic study of the Hall conductance in Bi$_2$Sr$_2$CaCu$_2$O$_x$ (Bi2212) thin films over a large range of doping. We find that in a large part of the phase diagram the Hall coefficient changes sign as a function of temperature in the flux-flow regime. By comparing data from many samples, we show that the sign reversal is tied to the superconducting transition and is not a result of a competing order. We then compare our data to the predictions of the Bardeen-Stephan model and show that in all samples there is an additional negative contribution to the Hall conductivity. We extract from the negative excess Hall a vortex-charge that is found to be strongly doping dependent.

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Yuval Nitzav, Amit Kanigel. 2023-04-06. Hall anomaly and vortex charge in Bi$_2$Sr$_2$CaCu$_2$O$_x$. https://doi.org/10.1103/physrevb.107.094516

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