TY - JOUR
T1 - In-plane hexagonal antiferromagnet in the Cu-Mn-As system Cu0.82Mn1.18As
AU - Karigerasi, Manohar H.
AU - Kang, Kisung
AU - Ramanathan, Arun
AU - Gray, Danielle L.
AU - Frontzek, Matthias D.
AU - Cao, Huibo
AU - Schleife, André
AU - Shoemaker, Daniel P.
N1 - Publisher Copyright:
© 2019 American Physical Society.
PY - 2019/11/27
Y1 - 2019/11/27
N2 - We report the single-crystal growth and characterization of a hexagonal phase Cu0.82Mn1.18As, in the Cu-Mn-As system. This compound contains the same square-pyramidal MnAs5 units as the tetragonal and orthorhombic polymorphs of CuMnAs. Calorimetry, magnetometry, and neutron diffraction measurements reveal antiferromagnetic ordering at 270 K. The magnetic structure consists of a triangular arrangement of spins in the ab plane. Hexagonal Cu0.82Mn1.18As shows resistivity that varies only weakly from 5 to 300 K, and is many times higher than tetragonal CuMnAs, indicative of a strongly scattering metal. First-principles calculations confirm the metallic band structure with a small density of states at the Fermi energy. The neutron-refined magnetic ground state is close to the computationally determined minimum energy configuration. This compound should serve as a clear control when disentangling the effects of current-driven Néel switching of metallic antiferromagnets since it exhibits in-plane spins but the magnetic ordering does not break degeneracy along the a and b directions, unlike tetragonal CuMnAs.
AB - We report the single-crystal growth and characterization of a hexagonal phase Cu0.82Mn1.18As, in the Cu-Mn-As system. This compound contains the same square-pyramidal MnAs5 units as the tetragonal and orthorhombic polymorphs of CuMnAs. Calorimetry, magnetometry, and neutron diffraction measurements reveal antiferromagnetic ordering at 270 K. The magnetic structure consists of a triangular arrangement of spins in the ab plane. Hexagonal Cu0.82Mn1.18As shows resistivity that varies only weakly from 5 to 300 K, and is many times higher than tetragonal CuMnAs, indicative of a strongly scattering metal. First-principles calculations confirm the metallic band structure with a small density of states at the Fermi energy. The neutron-refined magnetic ground state is close to the computationally determined minimum energy configuration. This compound should serve as a clear control when disentangling the effects of current-driven Néel switching of metallic antiferromagnets since it exhibits in-plane spins but the magnetic ordering does not break degeneracy along the a and b directions, unlike tetragonal CuMnAs.
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U2 - 10.1103/PhysRevMaterials.3.111402
DO - 10.1103/PhysRevMaterials.3.111402
M3 - Article
AN - SCOPUS:85076421575
SN - 2475-9953
VL - 3
JO - Physical Review Materials
JF - Physical Review Materials
IS - 11
M1 - 111402
ER -