Abstract
The tetragonal intermetallic compound EuAl4 hosts an exciting variety of low-temperature phases. In addition to a charge density wave below 140 K, four ordered magnetic phases are observed below 15.4 K in zero field. Recently, a skyrmion phase was proposed based on Hall effect measurements under a c-axis magnetic field. We present a detailed investigation of the phase transitions in EuAl4 under c-axis magnetic field. Our dilatometry, heat-capacity, DC magnetometry, AC magnetic susceptibility, and resonant ultrasound spectroscopy measurements reveal three magnetic phase transitions not previously reported. The first key result is a detailed H∥[001] magnetic phase diagram mapping the seven phases we observe. Second, we identify a high-field phase, phase VII, which directly corresponds to the region were skyrmions have been previously suggested. Our results provide guidance for future studies exploring the complex magnetic interactions and spin structures in EuAl4.
| Original language | English |
|---|---|
| Article number | 094421 |
| Journal | Physical Review B |
| Volume | 106 |
| Issue number | 9 |
| DOIs | |
| State | Published - Sep 1 2022 |
Funding
We would like to thank C. Batista, S. Gao, S. Do, and A. Christianson for their helpful discussions about topological magnetic textures. We would like to thank B. Chakoumakos for his low-temperature single-crystal XRD measurements. M.Y. Hu and E. E. Alp (Argonne) are acknowledged for assistance for NRIXS data acquisition at 3-ID. Research was supported by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, Materials Sciences and Engineering Division (under Contract No. DE-AC05-00OR22725). J.R.T. was supported by ORNL Laboratory Directed Research and Development (LDRD) funds. W.R.M. acknowledges partial support for writing from the Gordon and Betty Moore Foundation's EPiQS Initiative, Grant No. GBMF9069. This research used resources of the Advanced Photon Source, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract No. DE-AC02-06CH11357. This manuscript has been authored by UT-Battelle, LLC, under Contract No. DE-AC05-00OR22725 with the U.S. Department of Energy. The United States Government retains and the publisher, by accepting the article for publication, acknowledges that the United States Government retains a nonexclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for United States Government purposes. The Department of Energy will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan .
| Funders | Funder number |
|---|---|
| U.S. Department of Energy | |
| Gordon and Betty Moore Foundation | GBMF9069 |
| Office of Science | |
| Basic Energy Sciences | |
| Argonne National Laboratory | DE-AC02-06CH11357 |
| Laboratory Directed Research and Development | |
| Division of Materials Sciences and Engineering | DE-AC05-00OR22725 |