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arXiv · 2201.07455

Slow Electronic Dynamics in the Paramagnetic State of UTe$_2$

Yo Tokunaga·Hironori Sakai·Shinsaku Kambe·Yoshinori Haga·Yoshifumi Tokiwa·Petr Opletal·Hiroki Fujibayashi·Katsuki Kinjo·Shunsaku Kitagawa·Kenji Ishida·Ai Nakamura·Yusei Shimizu·Yoshiya Homma·Dexin Li·Fuminori Honda·Dai Aoki
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Abstract

$^{125}$Te NMR experiments in field ($H$) applied along the easy magnetization axis (the $a$-axis) revealed slow electronic dynamics developing in the paramagnetic state of UTe$_2$. The observed slow fluctuations are concerned with a successive growth of long-range electronic correlations below 30$-$40 K, where the spin susceptibility along the hard magnetization axis (the $b$-axis) shows a broad maximum. The experiments also imply that tiny amounts of disorder or defects locally disturb the long-range electronic correlations and develop an inhomogeneous electronic state at low temperatures, leading to a low temperature upturn observed in the bulk-susceptibility in $H\|a$. We suggest that UTe$_2$ would be located on the paramagnetic side near an electronic phase boundary, where either magnetic or Fermi-surface instability would be the origin of the characteristic fluctuations.

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Yo Tokunaga, Hironori Sakai, Shinsaku Kambe, Yoshinori Haga, Yoshifumi Tokiwa, Petr Opletal, Hiroki Fujibayashi, Katsuki Kinjo, Shunsaku Kitagawa, Kenji Ishida, Ai Nakamura, Yusei Shimizu, Yoshiya Homma, Dexin Li, Fuminori Honda, Dai Aoki. 2022-01-19. Slow Electronic Dynamics in the Paramagnetic State of UTe$_2$. https://doi.org/10.7566/jpsj.91.023707

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