Abstract
We investigated the magnetic structure of the heavy-fermion compound below K using magnetic resonant x-ray diffraction at ambient pressure. The magnetic order is characterized by a commensurate propagation vector with spins lying in the basal plane. Our measurements did not reveal the presence of an incommensurate order propagating along the high-symmetry directions in reciprocal space but cannot exclude other incommensurate modulations or weak scattering intensities. The observed commensurate order can be described equivalently by either a single- structure or by a multi- structure. Furthermore we explain how a commensurate-only ordering may explain the broad distribution of internal fields observed in nuclear quadrupolar resonance experiments [Sakai et al., Phys. Rev. B 83, 140408 (2011)] that was previously attributed to an incommensurate order. We also report powder x-ray diffraction showing that the crystallographic structure of changes monotonically with pressure up to GPa at room temperature. The determined bulk modulus GPa is similar to those of the Ce-115 family. Broad diffraction peaks confirm the presence of pronounced strain in polycrystalline samples of . We discuss how strain effects can lead to different electronic and magnetic properties between polycrystalline and single crystal samples.
- Received 24 April 2017
- Revised 19 July 2017
DOI:https://doi.org/10.1103/PhysRevB.96.064414
©2017 American Physical Society