We report the physical properties of orthorhombic o-CuMnAs single crystal, which is predicted to be a topological Dirac semimetal with magnetic ground state and inversion symmetry broken. o-CuMnAs exhibits an antiferromagnetic transition with TN ~ 312 K. Further characterizations of magnetic properties suggest that the AFM order may be canted with the spin orientation in the bc plane. Small isotropic MR and linearly field-dependent Hall resistivity with positive slope indicate that single hole-type carries with high density and low mobility dominate the transport properties of o-CuMnAs. Furthermore, the result of low-temperature heat capacity shows that the effective mass of carriers is much larger than those in typical topological semimetals. These results imply that the carriers in o-CuMnAs exhibit remarkably different features from those of Dirac fermions predicted in theory.
@article{arxiv.1709.03394,
title = {Massive fermions with low mobility in antiferromagnet orthorhombic CuMnAs single crystals},
author = {Xiao Zhang and Shanshan Sun and Hechang Lei},
journal= {arXiv preprint arXiv:1709.03394},
year = {2017}
}