arXiv 1705.080982017-05-23cond-mat.supr-con

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

发表信息：: Phys. Rev. B 96, 041111 (2017)
DOI：: 10.1103/PhysRevB.96.041111

英文摘要：

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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