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arXiv · 2107.13914

Feedback of superconductivity on the magnetic excitation spectrum of UTe$_{2}$

S. Raymond·W. Knafo·G. Knebel·K. Kaneko·J. -P. Brison·J. Flouquet·D. Aoki·G. Lapertot
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Abstract

We investigate the spin dynamics in the superconducting phase of UTe$_{2}$ by triple-axis inelastic neutron scattering on a single crystal sample. At the wave-vector $\bf{k_1}$=(0, 0.57, 0), where the normal state antiferromagnetic correlations are peaked, a modification of the excitation spectrum is evidenced, on crossing the superconducting transition, with a reduction of the relaxation rate together with the development of an inelastic peak at $\Omega$ $\approx$ 1 meV. The low dimensional nature and the the $a$-axis polarization of the fluctuations, that characterise the normal state, are essentially maintained below $T_{sc}$. The high ratio $\Omega/k_{B}T_{sc}$ $\approx$ 7.2 contrasts with the most common behaviour in heavy fermion superconductors.

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S. Raymond, W. Knafo, G. Knebel, K. Kaneko, J. -P. Brison, J. Flouquet, D. Aoki, G. Lapertot. 2021-07-29. Feedback of superconductivity on the magnetic excitation spectrum of UTe$_{2}$. https://doi.org/10.7566/jpsj.90.113706

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