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arXiv · 2407.21232

Test of the Equivalence Principle for Superconductors

M. P. Ross·S. M. Fleischer·I. A. Paulson·P. Lamb·B. M. Iritani·E. G. Adelberger·C. A. Hagedorn·K. Venkateswara·C. Gettings·E. A. Shaw·S. K. Apple·J. H. Gundlach
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Abstract

We searched for violations of the weak equivalence principle using a cryogenic torsion balance with a pendulum comprised of superconducting niobium and copper. We constrain the E\"otv\"os parameter with 95%-confidence to $\eta_{\text{Nb*-Cu}}~\leq~2.0\times10^{-9}$ and $\eta_{\text{CP-ee}}\leq9.2\times10^{-4}$ for superconducting niobium and Cooper pairs, respectively.

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M. P. Ross, S. M. Fleischer, I. A. Paulson, P. Lamb, B. M. Iritani, E. G. Adelberger, C. A. Hagedorn, K. Venkateswara, C. Gettings, E. A. Shaw, S. K. Apple, J. H. Gundlach. 2024-07-30. Test of the Equivalence Principle for Superconductors. https://arxiv.org/abs/2407.21232

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