Probing of magnetic anisotropy in heavy fermion system Ce3Co4Sn13 with neutron powder diffraction in magnetic field

The heavy fermion system Ce3Co4Sn13 has been attracting considerable interest due its puzzling magnetic ground state. It crystallizes in cubic Pm-3n space group with Ce atoms forming three-dimensional frustrated exchange topology. This makes Ce3Co4Sn13 a model system to study interplay between RKKY and Kondo interactions under the presence of geometrical frustration. In spite of the clear anomaly in the specific heat data around 0.7K, no evidence of long range magnetic order has been found in our previous single crystal neutron diffraction experiment on WISH. Two possible scenarios can be proposed to explain the lack of long-range magnetic order. Both of them rely on a strong single ion anisotropy, with the anisotropy easy axis for one of them and easy plane for the other. Surprisingly, our inelastic neutron scattering data could not resolve the issue, since the data were equally well fitted by two sets of the crystal electric field parameters with different type of the magnetic anisotropy. The different anisotropy, however, implies different magnetization process, which we are going to probe using neutron powder diffraction in magnetic field.