Exotic magnetic phase diagram and extremely robust antiferromagnetism in Ce$_2$RhIn$_8$

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Klein, T., Marcenat, C., Demuer, A., Sarrade, J., Aoki, D., Sheikin, I.
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866912378696761344
author Klein, T.
Marcenat, C.
Demuer, A.
Sarrade, J.
Aoki, D.
Sheikin, I.
author_facet Klein, T.
Marcenat, C.
Demuer, A.
Sarrade, J.
Aoki, D.
Sheikin, I.
contents The antiferromagnetic heavy-fermion compound Ce$_2$RhIn$_8$ belongs to the same family and bears similarities with the well-studied prototypical material CeRhIn$_5$, which demonstrates a unique behavior under applied magnetic field. Here, we report specific-heat measurements on a high-quality single crystal of Ce$_2$RhIn$_8$ in magnetic fields up to 35 T applied along both principal crystallographic directions. When the magnetic field is applied along the $a$ axis of the tetragonal crystal structure, two additional field-induced antiferromagnetic phases are observed, in agreement with previous reports. One of them is confined in a small area of the field-temperature phase diagram. The other one, which develops above $\sim$2.5 T, is very robust against the field. Its transition temperature increases with field, reaches a maximum at $\sim$12 T, and then starts to decrease. However, it tends to saturate towards the highest field of our measurements. For a field applied along the $c$ axis, the Néel temperature, $T_N$, initially decreases with field, as expected for a typical antiferromagnet. Surprisingly, an additional phase emerges above $\sim$10 T. It is most likely to be of the same origin as its counterpart observed above 2.5 T for the other field orientation. This phase is also unusually robust: Its transition temperature increases all the way up to 35 T, where it exceeds the zero field $T_N =$~2.85 K. Finally, for both field directions, the phase diagrams contain rarely observed tricritical points of second-order phase transitions.
format Preprint
id arxiv_https___arxiv_org_abs_2505_04238
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Exotic magnetic phase diagram and extremely robust antiferromagnetism in Ce$_2$RhIn$_8$
Klein, T.
Marcenat, C.
Demuer, A.
Sarrade, J.
Aoki, D.
Sheikin, I.
Strongly Correlated Electrons
The antiferromagnetic heavy-fermion compound Ce$_2$RhIn$_8$ belongs to the same family and bears similarities with the well-studied prototypical material CeRhIn$_5$, which demonstrates a unique behavior under applied magnetic field. Here, we report specific-heat measurements on a high-quality single crystal of Ce$_2$RhIn$_8$ in magnetic fields up to 35 T applied along both principal crystallographic directions. When the magnetic field is applied along the $a$ axis of the tetragonal crystal structure, two additional field-induced antiferromagnetic phases are observed, in agreement with previous reports. One of them is confined in a small area of the field-temperature phase diagram. The other one, which develops above $\sim$2.5 T, is very robust against the field. Its transition temperature increases with field, reaches a maximum at $\sim$12 T, and then starts to decrease. However, it tends to saturate towards the highest field of our measurements. For a field applied along the $c$ axis, the Néel temperature, $T_N$, initially decreases with field, as expected for a typical antiferromagnet. Surprisingly, an additional phase emerges above $\sim$10 T. It is most likely to be of the same origin as its counterpart observed above 2.5 T for the other field orientation. This phase is also unusually robust: Its transition temperature increases all the way up to 35 T, where it exceeds the zero field $T_N =$~2.85 K. Finally, for both field directions, the phase diagrams contain rarely observed tricritical points of second-order phase transitions.
title Exotic magnetic phase diagram and extremely robust antiferromagnetism in Ce$_2$RhIn$_8$
topic Strongly Correlated Electrons
url https://arxiv.org/abs/2505.04238