Neutron diffraction study on heavy-fermion compound CeCrGe3

We present a comprehensive powder neutron diffraction study on the heavy-fermion Kondo lattice system CeCrGe3 which orders ferromagnetically below TC=70K. The neutron diffraction data corroborate the presence of magnetic Bragg peaks below TC which could be indexed with the propagation vector k - =(000). Due to the presence of a very few magnetic reflections at low T, we have used ratio of intensities between the temperatures below (10 K) and above TC (80 K) to analyze magnetic structure, rather than the conventional Rietveld refinement method. Our analysis of the magnetic structure reveals an ordered magnetic moment of 1.1(1) μB for the Cr moments and 0.8(2) μB for the Ce moments where both are aligned in the ab plane at T=10K. Remarkably, the presence of Ce moment is found to have a strong correlation with Cr moment and sets the Cr moments to order in the ab plane rather than along the c axis which was seen in 4f0 counterpart, i.e., LaCrGe3.