Simultaneous collapse of antiferroquadrupolar order and superconductivity in PrIr$_{2}$Zn$_{20}$ by nonhydrostatic pressure

TL;DR

This study investigates how nonhydrostatic pressure suppresses both antiferroquadrupolar order and superconductivity in PrIr₂Zn₂₀, revealing the role of quadrupolar fluctuations in inducing superconductivity.

Contribution

It demonstrates the contrasting effects of hydrostatic and nonhydrostatic pressures on the order parameters and superconductivity in PrIr₂Zn₂₀, highlighting the importance of quadrupolar fluctuations.

Findings

Hydrostatic pressure increases T_Q but leaves T_c nearly unchanged.

Nonhydrostatic pressure suppresses both T_Q and T_c below 0.04 K.

Quadrupolar fluctuations are crucial for superconductivity in this material.

Abstract

Superconductivity in PrIr$_{2}$Zn$_{20}$ appears at $T_{\rm c} = 0.05$ K in the presence of an antiferroquadrupolar order below $T_{\rm Q} = 0.11$ K. We have studied pressure dependences of $T_{\rm c}$, $T_{\rm Q}$, and non-Fermi liquid behaviors in the resistivity $\rho (T)$ by using two pressure transmitting media: argon maintaining highly hydrostatic pressure, and glycerol, which solidifies above 5 GPa producing nonhydrostatic pressure. Upon applying $P$ with argon up to 10.6 GPa, $T_{\rm c}$ hardly changes, while $T_{\rm Q}$ monotonically increases from 0.11 to 0.23 K. With glycerol, however, $T_{\rm Q}$ and $T_{\rm c}$ simultaneously fall below 0.04 K at 6.3 GPa. The contrasting results indicate that onsite quadrupolar fluctuations induce superconductivity in this compound.