Pressure-induced amorphization and enhanced magnetic order in EuSn<sub>2</sub>As<sub>2</sub>

ORAL

Abstract

In this work, we investigated the influence of pressure on a layered magnetic topological insulator EuSn2As2 by experimental probes including synchrotron X-ray diffraction (XRD), X-ray absorption (XAS), and Mössbauer spectroscopy (SMS) combined with theoretical calculations. EuSn2As2 undergoes a pressure-induced amorphization under the pressure of 30 GPa coinciding with a valence transition from Eu2+ toward Eu3+. High-pressure and low-temperature SMS in 151Eu has been adopted to study the magnetic state up to 33 GPa. The experimental data were further supported by theoretical analysis. Additionally, we reveal that the magnetic ordering temperature is largely enhanced reaching 110 K at 26 GPa from 25 K at ambient pressure. The mechanism of the pressure-induced amorphization and enhanced magnetic order as well as the correlation with valence transition will be discussed in detail.

*This work is supported by the National Science Foundation through Grant No. OIA- 2033131. This research used resources of the Advanced Photon Source (APS), Argonne National Laboratory (ANL), 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.

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Publication: 1. Synergizing high valence rare-earth sites and amorphization to preserve robust magnetic state in EuSn2As2 (planned paper)

Presenters

  • Sudeshna Samanta

    • University of Alabama Bbirmingham

Authors

  • Sudeshna Samanta

    • University of Alabama Bbirmingham

  • Wenli Bi

    • University of Alabama at Birmingham

  • Yansun Yao

    • Department of Physics and Engineering Physics, University of Saskatchewan, Saskatoon, Saskatchewan S7N5E2, Canada

  • Weiwei Xie

    • Department of Chemistry and Chemical Biology, The State University of New Jersey-Rutgers, Piscataway, NJ 08854 USA

  • Wei Xu

    • Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing, 100049, China

  • Jiyong Zhao

    • Argonne National Laboratory
    • Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439, USA

  • Esen E. Alp

    • Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439, USA

  • Dongzhou Zhang

    • University of Hawaii at Manoa
    • Hawaii Institute of Geophysics and Planetology, School of Ocean and Earth Science and Technology, University of Hawaii at Manoa, Honolulu, Hawaii 96822, USA

  • Jingui Xu

    • University of Hawaii at Manoa
    • Hawaii Institute of Geophysics and Planetology, School of Ocean and Earth Science and Technology, University of Hawaii at Manoa, Honolulu, Hawaii 96822, USA

  • Yuming Xiao

    • Argonne National Laboratory
    • HPCAT, X-ray Science Division, Argonne National Laboratory, Argonne, Illinois 60439, USA

  • Yogesh K Vohra

    • University of Alabama at Birmingham
    • Department of Physics, University of Alabama at Birmingham, Birmingham, AL, 35294, USA