Crystal structure, magnetic ordering, and magnetic excitation in the 4f-localized ferromagnet CeAgSb2

Shingo Araki, Naoto Metoki, Andrei Galatanu, Etsuji Yamamoto, Yoshichika Ōnuki, Yoshichika Ōnuki

Research output: Contribution to journalArticle

34 Citations (Scopus)

Abstract

Systematic neutron-scattering experiments have been carried out in order to reveal the crystal and magnetic structures as well as the magnetic excitation in the Ce-based intermetallic compound CeAgSb2. It was clarified that the Ag atoms in CeAgSb2(space group: P4/nmm) occupy the 2b site, while Sb atoms occupy 2a and 2c sites, which have, to date, been controversial in literature. From the analysis of neutron powder-diffraction profile, we found the existence of the ferromagnetic component of about 0.41μB/Ce oriented along the c axis, consistent with the result of previous studies. On the other hand, however, no trace of the antiferromagnetic or spin-density wave peak was detected within our range of experimental accuracy. We observed a considerable spin-wave excitation below 3 meV. The dispersion relation was explained by the anisotropic Heisenberg model. This means that CeAgSb2 has a simple ferromagnetic structure. Furthermore, crystalline electric-field (CEF) excitations were observed at 5.2 and 12.5 meV in the paramagnetic state, which is indicative of the localized nature of the Ce-4f electron. Our analysis revealed that formul presented is the ground state, while the first and second excited levels are mainly due to formul presented, respectively. The observed ferromagnetic moment is in good agreement with the ground-state saturation moment, gJμBJz∼0.43μB. The susceptibility, magnetization curve, and magnetostriction can be explained in terms of the CEF level scheme with anisotropic exchange interaction.

Original languageEnglish
JournalPhysical Review B - Condensed Matter and Materials Physics
Volume68
Issue number2
DOIs
Publication statusPublished - Jan 1 2003
Externally publishedYes

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics

Fingerprint Dive into the research topics of 'Crystal structure, magnetic ordering, and magnetic excitation in the 4f-localized ferromagnet CeAgSb<sub>2</sub>'. Together they form a unique fingerprint.

  • Cite this