Abstract
Determination of the magnetic structure and confirmation of the presence or absence of inversion(P)and time reversal(T)symmetry is imperative for correctly understanding the topological magnetic materials.Here high-quality single crystals of the layered manganese pnictide CaMnSb2 are synthesized using the self-flux method.De Haas-van Alphen oscillations indicate a nontrivial Berry phase of～π and a notably small cyclotron effective mass,supporting the Dirac semimetal nature of CaMnSb2.Neutron diffraction measurements identify a C-type antiferromagnetic structure below TN=303(1)K with the Mn moments aligned along the a axis,which is well supported by the density functional theory(DFT)calculations.The corresponding magnetic space group is Pn'm'a',preserving a P × T symmetry.Adopting the experimentally determined magnetic structure,band crossings near the Y point in momentum space and linear dispersions of the Sb 5py,z bands are revealed by the DFT calculations.Furthermore,our study predicts the possible existence of an intrinsic second-order nonlinear Hall effect in CaMnSb2,offering a promising platform to study the impact of topological properties on nonlinear electrical transports in antiferromagnets.
基金项目
国家自然科学基金(12074023)
国家自然科学基金(12304053)
国家自然科学基金(12174018)
Large Scientific Facility Open Subject of Songshan Lake(Dongguan,Guangdong)()
中央高校基本科研业务费专项()
万方数据