Superconductivity of cerium under pressures up to 54GPa

TL;DR

This study investigates how applying high pressure up to 54 GPa induces structural transitions in cerium, leading to the emergence and evolution of superconductivity with a maximum $T_c$ of 1.25 K, revealing the link between structure and electronic states.

Contribution

It provides a detailed transport analysis of cerium's superconductivity under pressure, highlighting the correlation with structural phase transitions and electronic structure changes.

Findings

Superconductivity appears at 4.9 GPa with $T_c$ of 0.4 K.

$T_c$ increases to 0.5 K at 11.4 GPa.

Maximum $T_c$ of 1.25 K occurs at 17.2 GPa.

Abstract

Cerium is a fascinating element due to its diverse physical properties, which include forming various crystal structures ($\gamma$, $\alpha$, $\alpha^{'}$, $\alpha^{''}$ and $\epsilon$), mixed valence behavior and superconductivity, making it an ideal platform for investigating the interplay between different electronic states. Here, we present a comprehensive transport study of cerium under hydrostatic pressures up to 54 GPa. Upon applying pressure, cerium undergoes the $\alpha$ $\rightarrow$ $\alpha^{''}$ transition at around 4.9 GPa, which is accompanied by the appearance of superconductivity with $T_{\rm c}$ of 0.4 K, and $T_{\rm c}$ slightly increases to 0.5 K at 11.4 GPa. At 14.3 GPa, $T_{\rm c}$ suddenly increases when the $\alpha^{''}$ phase transforms into the $\epsilon$ phase, reaching a maximum value of 1.25 K at around 17.2 GPa. Upon further increasing the pressure, $T_{\rm c}$ monotonically decreases. Together with the results of previous studies, our findings suggest that the evolution of superconductivity in cerium is closely correlated with the multiple pressure-induced structural transitions and corresponding unusual electronic structures.