Universal scaling law for chiral antiferromagnetism

Abstract

The chiral antiferromagnetic (AFM) materials, which have been widely investigated due to their rich physics, such as non-zero Berry phase and topology, provide a platform for the development of antiferromagnetic spintronics. Here, we find two distinctive anomalous Hall effect (AHE) contributions in the chiral AFM Mn₃Pt, originating from a time-reversal symmetry breaking induced intrinsic mechanism and a skew scattering induced topological AHE due to an out-of-plane spin canting with respect to the Kagome plane. We propose a universal AHE scaling law to explain the AHE resistivity ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub><mml:mrow><mml:mi>ρ</mml:mi></mml:mrow> <mml:mrow><mml:mi>A</mml:mi> <mml:mi>H</mml:mi></mml:mrow> </mml:msub> </mml:math> ) in this chiral magnet, with both a scalar spin chirality (SSC)-induced skew scattering topological AHE term, <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub><mml:mrow><mml:mi>a</mml:mi></mml:mrow> <mml:mrow><mml:mi>s</mml:mi> <mml:mi>k</mml:mi></mml:mrow> </mml:msub> </mml:math> and non-collinear spin-texture induced intrinsic anomalous Hall term, <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub><mml:mrow><mml:mi>b</mml:mi></mml:mrow> <mml:mrow><mml:mi>i</mml:mi> <mml:mi>n</mml:mi></mml:mrow> </mml:msub> </mml:math> . We found that <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub><mml:mrow><mml:mi>a</mml:mi></mml:mrow> <mml:mrow><mml:mi>s</mml:mi> <mml:mi>k</mml:mi></mml:mrow> </mml:msub> </mml:math> and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub><mml:mrow><mml:mi>b</mml:mi></mml:mrow> <mml:mrow><mml:mi>i</mml:mi> <mml:mi>n</mml:mi></mml:mrow> </mml:msub> </mml:math> can be effectively modulated by the interfacial electron scattering, exhibiting a linear relation with the inverse film thickness. Moreover, the scaling law can explain the anomalous Hall effect in various chiral magnets and has far-reaching implications for chiral-based spintronics devices.