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arXiv · 1906.01303

125Te-NMR Study on a Single Crystal of Heavy Fermion Superconductor UTe2

Yo Tokunaga·Hironori Sakai·Shinsaku Kambe·Taisuke Hattori·Nonoka Higa·Genki Nakamine·Shunsaku Kitagawa·Kenji Ishida·Ai Nakamura·Yusei Shimizu·Yoshiya Homma·DeXin Li·Fuminori Honda·Dai Aoki
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Abstract

We report 125Te-NMR studies on a newly discovered heavy fermion superconductor UTe2. Using a single crystal, we have measured the 125Te-NMR Knight shift K and spin-lattice relaxation rate 1/T1 for fields along the three orthorhombic crystal axes. The data confirm a moderate Ising anisotropy for both the static (K) and dynamical susceptibilities (1/T1) in the paramagnetic state above about 20 K. Around 20 K, however, we have observed a sudden loss of NMR spin-echo signal due to sudden enhancement of the NMR spin-spin relaxation rate 1/T2, when the field is applied along the easy axis of magnetization (=a axis). This behavior suggests the development of longitudinal magnetic fluctuations along the a axis at very low frequencies below 20 K.

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Yo Tokunaga, Hironori Sakai, Shinsaku Kambe, Taisuke Hattori, Nonoka Higa, Genki Nakamine, Shunsaku Kitagawa, Kenji Ishida, Ai Nakamura, Yusei Shimizu, Yoshiya Homma, DeXin Li, Fuminori Honda, Dai Aoki. 2019-06-04. 125Te-NMR Study on a Single Crystal of Heavy Fermion Superconductor UTe2. https://doi.org/10.7566/jpsj.88.073701

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