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arXiv · 2112.13468

Effect of uranium deficiency on normal and superconducting properties in unconventional superconductor UTe$_2$

Y. Haga·P. Opletal·Y. Tokiwa·E. Yamamoto·Y. Tokunaga·S. Kambe·H. Sakai
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Abstract

Single crystals of the unconventional superconductor UTe$_2$ have been grown in various conditions which result in different superconducting transition temperature as well as normal state properties. Stoichiometry of the samples has been characterized by the single-crystal X-ray crystallography and electron microprobe analyses. Superconducting samples are nearly stoichiometric within an experimental error of about 1 \%, while non-superconducting sample significantly deviates from the ideal composition. The superconducting UTe$_2$ showed that the large density of states was partially gapped in the normal state, while the non-superconducting sample is characterized by the relatively large electronic specific heat as reported previously.

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Y. Haga, P. Opletal, Y. Tokiwa, E. Yamamoto, Y. Tokunaga, S. Kambe, H. Sakai. 2022-03-10. Effect of uranium deficiency on normal and superconducting properties in unconventional superconductor UTe$_2$. https://doi.org/10.1088/1361-648x%2Fac5201

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