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arXiv · 1907.08645

Physical properties of $R$Bi$_2$ ($R=$La, Ce) under pressure

Li Xiang·Elena Gati·Kathryn Neilson·Sergey L. Bud'ko·Paul C. Canfield
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Abstract

We present a study of electrical transport properties of $R$Bi$_2$ ($R$ = La, Ce) under hydrostatic pressure up to $\sim$ 2.5 GPa. These measurements are complemented by thermodynamic measurements of the specific heat on CeBi$_2$ at different pressures up to 2.55 GPa. For CeBi$_2$, we find a moderate increase of the antiferromagnetic transition, $T_\text N$, from 3.3 K to 4.4 K by pressures up to 2.55 GPa. Notably, resistance measurements for both CeBi$_2$ and LaBi$_2$ show signatures of superconductivity for pressures above $\sim$ 1.7 GPa. However, the absence of superconducting feature in specific heat measurements for CeBi$_2$ indicates that superconductivity in CeBi$_2$ (and most likely LaBi$_2$ as well) is not bulk and likely originates from traces of Bi flux, either on the surface of the plate-like samples, or trapped inside the sample as laminar inclusions.

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Li Xiang, Elena Gati, Kathryn Neilson, Sergey L. Bud'ko, Paul C. Canfield. 2019-07-19. Physical properties of $R$Bi$_2$ ($R=$La, Ce) under pressure. https://doi.org/10.1103/physrevmaterials.3.095006

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