Magnetic structure of CeGaGe

CeGaGe is a candidate Weyl semimetal material that crystallizes in the noncentrosymmetric space group 109 (I4₁md). Depending on growth conditions, we find that samples can be driven into a structure with symmetry given by space group 76 (P4₁) or its enantiomer, space group 78 (P4₃), below T=100 K [1]. In all samples, there is a clear phase transition into a magnetically ordered state at T_C≈5.5 K seen in magnetization and magnetic susceptibility, specific heat, and resistivity [2].



We present the results of a neutron powder diffraction experiment that determines the magnetic structure for CeGaGe when grown using the flux technique. We analyze the scattering data assuming each of the two closely related crystal symmetries, space group 109 and space group 78. The ordered magnetic structures determined by assuming the two different space groups are significantly different, but the structure determined in either crystal symmetry agrees reasonably well with previously reported magnetometry data [2].



[1] L. Scanlon et al., in prep. (2024)

[2] D. Ram, S. Malick, Z. Hossain, and D. Kaczorowski, Phys. Rev. B 108, 024428 (2023).