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arXiv · 1705.08098

Spin Susceptibility of the Topological Superconductor UPt3 from Polarized Neutron Diffraction

W. J. Gannon·W. P. Halperin·M. R. Eskildsen·Pengcheng Dai·U. B. Hansen·K. Lefmann·A. Stunault
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Abstract

Experiment and theory indicate that UPt3 is a topological superconductor in an odd-parity state, based in part from temperature independence of the NMR Knight shift. However, quasiparticle spin-flip scattering near a surface, where the Knight shift is measured, might be responsible. We use polarized neutron scattering to measure the bulk susceptibility with H||c, finding consistency with the Knight shift but inconsistent with theory for this field orientation. We infer that neither spin susceptibility nor Knight shift are a reliable indication of odd-parity.

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W. J. Gannon, W. P. Halperin, M. R. Eskildsen, Pengcheng Dai, U. B. Hansen, K. Lefmann, A. Stunault. 2017-05-23. Spin Susceptibility of the Topological Superconductor UPt3 from Polarized Neutron Diffraction. https://doi.org/10.1103/physrevb.96.041111

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