Planar triangular magnet: Magnetic frustration, short range correlations, and field-tuned anisotropic cycloidal magnetic order

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • M. Baenitz - , Max Planck Institute for Chemical Physics of Solids (Author)
  • M. M. Piva - , Max Planck Institute for Chemical Physics of Solids (Author)
  • S. Luther - , Chair of Physics of High Magnetic Fields, Helmholtz-Zentrum Dresden-Rossendorf (Author)
  • J. Sichelschmidt - , Max Planck Institute for Chemical Physics of Solids (Author)
  • K. M. Ranjith - , Max Planck Institute for Chemical Physics of Solids (Author)
  • H. Dawczak-Dȩbicki - , Max Planck Institute for Chemical Physics of Solids (Author)
  • M. O. Ajeesh - , Max Planck Institute for Chemical Physics of Solids (Author)
  • S. J. Kim - , Max Planck Institute for Chemical Physics of Solids (Author)
  • G. Siemann - , University of St Andrews (Author)
  • C. Bigi - , University of St Andrews (Author)
  • P. Manuel - , Rutherford Appleton Laboratory (Author)
  • D. Khalyavin - , Rutherford Appleton Laboratory (Author)
  • D. A. Sokolov - , Max Planck Institute for Chemical Physics of Solids (Author)
  • P. Mokhtari - , Max Planck Institute for Chemical Physics of Solids (Author)
  • H. Zhang - , Max Planck Institute for Chemical Physics of Solids (Author)
  • H. Yasuoka - , Max Planck Institute for Chemical Physics of Solids (Author)
  • P. D.C. King - , University of St Andrews (Author)
  • G. Vinai - , National Institute for Nuclear Physics (Author)
  • V. Polewczyk - , National Institute for Nuclear Physics (Author)
  • P. Torelli - , National Institute for Nuclear Physics (Author)
  • J. Wosnitza - , Chair of Physics of High Magnetic Fields, Helmholtz-Zentrum Dresden-Rossendorf (Author)
  • U. Burkhardt - , Max Planck Institute for Chemical Physics of Solids (Author)
  • B. Schmidt - , Max Planck Institute for Chemical Physics of Solids (Author)
  • H. Rosner - , Max Planck Institute for Chemical Physics of Solids (Author)
  • S. Wirth - , Max Planck Institute for Chemical Physics of Solids (Author)
  • H. Kühne - , Helmholtz-Zentrum Dresden-Rossendorf (Author)
  • M. Nicklas - , Max Planck Institute for Chemical Physics of Solids (Author)
  • M. Schmidt - , Max Planck Institute for Chemical Physics of Solids (Author)

Abstract

Single crystals of the hexagonal triangular lattice compound have been grown by chemical vapor transport. The crystals have been carefully characterized and studied by magnetic susceptibility, magnetization, specific heat, and thermal expansion. In addition, we used Cr-electron spin resonance and neutron diffraction to probe the Cr magnetism microscopically. To obtain the electronic density of states, we employed x-ray absorption and resonant photoemission spectroscopy in combination with density functional theory calculations. Our studies evidence an anisotropic magnetic order below . Susceptibility data in small fields of about 1 T reveal an antiferromagnetic (AFM) type of order for , whereas for the data are reminiscent of a field-induced ferromagnetic (FM) structure. At low temperatures and for , the field-dependent magnetization and AC susceptibility data evidence a metamagnetic transition at , which is absent for . We assign this to a transition from a planar cycloidal spin structure at low fields to a planar fanlike arrangement above . A fully ferromagnetically polarized state is obtained above the saturation field of at 2 K with a magnetization of . For , monotonically increases and saturates at the same value at at 4.2 K. Above , the magnetic susceptibility and specific heat indicate signatures of two dimensional (2D) frustration related to the presence of planar ferromagnetic and antiferromagnetic exchange interactions. We found a pronounced nearly isotropic maximum in both properties at about , which is a clear fingerprint of short range correlations and emergent spin fluctuations. Calculations based on a planar 2D Heisenberg model support our experimental findings and suggest a predominant FM exchange among nearest and AFM exchange among third-nearest neighbors. Only a minor contribution might be assigned to the antisymmetric Dzyaloshinskii-Moriya interaction possibly related to the noncentrosymmetric polar space group . Due to these competing interactions, the magnetism in , in contrast to the oxygen-based delafossites, can be tuned by relatively small, experimentally accessible magnetic fields, allowing us to establish the complete anisotropic magnetic H-T phase diagram in detail.

Details

Original languageEnglish
Article number134410
JournalPhysical Review B
Volume104
Issue number13
Publication statusPublished - 1 Oct 2021
Peer-reviewedYes