Anomalous Pressure Dependence of magnetic Ordering Temperature in Tb to 141 GPa: Comparison with Gd and Dy

TL;DR

This study investigates the pressure-induced magnetic behavior of terbium (Tb) up to 141 GPa, revealing an anomalous increase in its magnetic ordering temperature at high pressures, similar to dysprosium (Dy), indicating an unconventional magnetic state.

Contribution

The paper provides the first high-pressure resistivity measurements of Tb up to 141 GPa, showing anomalous magnetic behavior and suggesting a transition to an unconventional magnetic state.

Findings

Tb's magnetic ordering temperature sharply increases above 53 GPa.

Tb exhibits an anomalously high magnetic ordering temperature at high pressures.

Results imply a pressure-induced unconventional magnetic state in Tb.

Abstract

In previous studies the pressure dependence of the magnetic ordering temperature $T_{\text{o}}$ of Dy was found to exhibit a sharp increase above its volume collapse pressure of 73 GPa, appearing to reach temperatures well above ambient at 157 GPa. In a search for a second such lanthanide, electrical resistivity measurements were carried out on neighboring Tb to 141 GPa over the temperature range 3.8 - 295 K. Below Tb's volume collapse pressure of 53 GPa, the pressure dependence $T_{\text{o}}(P)$ mirrors that of both Dy and Gd. However, at higher pressures $T_{\text{o}}(P)$ for Tb becomes highly anomalous. This result, together with the very strong suppression of superconductivity by dilute Tb ions in Y, suggests that extreme pressure transports Tb into an unconventional magnetic state with an anomalously high magnetic ordering temperature.