Pressure tuning of competing magnetic interactions in intermetallic CeFe_2
We use high-pressure magnetic x-ray diffraction and numerical simulation to determine the low-temperature magnetic phase diagram of stoichiometric CeFe_2. Near 1.5 GPa we find a transition from ferromagnetism to antiferromagnetism, accompanied by a rhombohedral distortion of the cubic Laves crystal lattice. By comparing pressure and chemical substitution we find that the phase transition is controlled by a shift of magnetic frustration from the Ce-Ce to the Fe-Fe sublattice. Notably the dominant Ce-Fe magnetic interaction, which sets the temperature scale for the onset of long-range order, remains satisfied throughout the phase diagram but does not determine the magnetic ground state. Our results illustrate the complexity of a system with multiple competing magnetic energy scales and lead to a general model for magnetism in cubic Laves phase intermetallic compounds.
Additional Information©2012 American Physical Society. (Received 1 May 2012; published 20 July 2012). The work at the University of Chicago was supported by NSF Grant No. DMR-0907025. The work at the Advanced Photon Source and Materials Science Division of Argonne National Laboratory was supported by the US Department of Energy Basic Energy Sciences under Contract No. NE-AC02-06CH11357. P.C.C.'s work was supported by the US Department of Energy, Office of Basic Energy Science, Division of Materials Sciences and Engineering. Ames Laboratory is operated for the US Department of Energy by Iowa State University under Contract No. DE-AC02-07CH11358.
Published - PhysRevB.86.014422.pdf