High-Field Magnetization of CeRu2Al10

TL;DR

This study investigates the high-field magnetization of CeRu2Al10 and its La-doped variants, revealing the magnetic phase diagram, critical fields for long-range order suppression, and supporting a singlet pair formation scenario.

Contribution

It provides the first high-field magnetization phase diagram for CeRu2Al10 and La-doped variants, confirming theoretical predictions and proposing a field-induced magnetic phase.

Findings

LRO disappears at ~50 T for x=1

Critical field decreases with La doping

Results support singlet pair formation scenario

Abstract

The magnetization measurements of CexLa1-xRu2Al10 (x = 1, 0.75) under the high magnetic field were performed in order to obtain the information for the long-range order (LRO) in CeRu2Al10. We successfully obtained the magnetic phase diagram of these two compounds for the applied magnetic field along the a-axis which is the magnetization easy axis, and found that the LRO for x = 1 disappears at ~50 T which is the critical field to the paramagnetic phase. For x = 0.75, the critical magnetic field decreases to ~37 T by La substitution. The magnetic phase diagram and magnetization curve are qualitatively consistent with the recent Hanzawa's mean field calculation results obtained by assuming the dimer of Ce ions whose crystalline electric field ground state has a large magnetic anisotropy. These results support the singlet pair formation scenario recently proposed by Tanida et al.. We also pointed out the possibility of the appearance of the field-induced magnetic phase between ~40 T and ~50 T for x = 1.