A pathway to improve Nb$_3$Sn for SRF accelerator cavities via Zr inclusion

M. Tripathi; M. S. Shakel; J. Lee; H. E. Elsayed-Ali; S. Posen; G. V. Eremeev

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arXiv · 2610.36479

A pathway to improve Nb$_3$Sn for SRF accelerator cavities via Zr inclusion

M. Tripathi·M. S. Shakel·J. Lee·H. E. Elsayed-Ali·S. Posen·G. V. Eremeev

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Abstract

Nb$_3$Sn has the potential to exceed the performance of niobium-based superconducting radio-frequency (SRF) cavities, both in particle accelerators and in high-$Q_0$ cavities operating in multi-tesla magnetic fields for axion dark matter searches. We studied how the incorporation of Zr into the Nb$_3$Sn matrix by co-sputtering affects the microstructure and superconducting properties of Nb$_3$Sn films. As the atomic fraction of Zr increased, the surface morphology improved and the bulk and surface void densities decreased. At the optimal Zr content, the superconducting properties improved and a thinner surface niobium oxide formed. These results identify co-sputtered Nb$_3$Sn:Zr as a promising material to advance the performance limits of SRF cavities.

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M. Tripathi, M. S. Shakel, J. Lee, H. E. Elsayed-Ali, S. Posen, G. V. Eremeev. 2026-10-27. A pathway to improve Nb$_3$Sn for SRF accelerator cavities via Zr inclusion. https://arxiv.org/abs/2610.36479

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