We report neutron-diffraction results on single-crystal CaMn2P2 containing corrugated Mn honeycomb layers and determine its ground-state magnetic structure. The diffraction patterns consist of prominent (1/6, 1/6, L) reciprocal lattice unit (r.l.u.; L = integer) magnetic Bragg reflections, whose temperature-dependent intensities are consistent with a first-order antiferromagnetic phase transition at the N\'eel temperature TN=70(1) K. Our analysis of the diffraction patterns reveals an in-plane 6×6 magnetic unit cell with ordered spins that in the principal-axis directions rotate by 60-degree steps between nearest neighbors on each sublattice that forms the honeycomb structure, consistent with the PAc magnetic space group. We find that a few other magnetic subgroup symmetries (PA2/c, PC2/m, PS1ˉ,PC2,PCm,PS1) of the paramagnetic P3ˉm11′ crystal symmetry are consistent with the observed diffraction pattern. We relate our findings to frustrated J1-J2-J3 Heisenberg honeycomb antiferromagnets with single-ion anisotropy and the emergence of Potts nematicity
@article{arxiv.2205.04492,
title = {Frustrated Magnetic Cycloidal Structure and Emergent Potts Nematicity in CaMn$_2$P$_2$},
author = {Farhan Islam and Thaís V. Trevisan and Thomas Heitmann and Santanu Pakhira and Simon X. M. Riberolles and N. S. Sangeetha and David C. Johnston and Peter P. Orth and David Vaknin},
journal= {arXiv preprint arXiv:2205.04492},
year = {2023}
}