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Title: Complex magnetic behavior of the sawtooth Fe chains in Rb2Fe2O(AsO4)2

Results of magnetic eld and temperature dependent neutron diraction and magnetization mea- surements on oxy-arsenate Rb2Fe2O(AsO4)2 are reported. The crystal structure of this compound contains pseudo-one-dimensional [Fe2O6] sawtooth-like chains, formed by corner sharing isosce- les triangles of Fe3+ ions occupying two nonequivalent crystallographic sites. The chains extend innitely along the crystallographic b-axis and are structurally conned from one another via dia- magnetic (AsO4)3- units along the a-axis, and Rb+ cations along the c-axis direction. Neutron diraction measurements indicate the onset of a long range antiferromagnetic order below approxi- mately 25 K. The magnetic structure consists of ferrimagnetic chains which are antiferromagnetically coupled with each other. Within each chain, one of the two Fe sites carries a moment which lies along the b-axis, while the second site bears a canted moment in the opposite direction. Exter- nally applied magnetic eld induces a transition to a ferrimagnetic state, in which the coupling between the sawtooth chains becomes ferromagnetic. Magnetization measurements performed on optically-aligned single crystals reveal evidence for an uncompensated magnetization at low mag- netic elds that could emerge from to a phase-segregated state with ferrimagnetic inclusions or from antiferromagnetic domain walls. The observed magnetic states and the competition between them ismore » expected to arise from strongly frustrated interactions within the sawtooth chains and relatively weak coupling between them.« less
 [1] ;  [2] ;  [1] ;  [3] ;  [2] ;  [2]
  1. ORNL
  2. Clemson University
  3. Indian Institute of Information Technology
Publication Date:
OSTI Identifier:
DOE Contract Number:
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review B; Journal Volume: 89; Journal Issue: 1
Research Org:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). High Flux Isotope Reactor (HFIR)
Sponsoring Org:
USDOE Office of Science (SC)
Country of Publication:
United States