Magnetic critical behavior and anomalous Hall effect in <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>2H</mml:mi><mml:mtext>−</mml:mtext><mml:msub><mml:mrow><mml:mi>Co</mml:mi></mml:mrow><mml:mrow><mml:mn>0.22</mml:mn></mml:mrow></mml:msub><mml:msub><mml:mrow><mml:mi>TaS</mml:mi></mml:mrow><mml:mn>2</mml:mn></mml:msub></mml:math> single crystals
Yu Liu, Zhixiang Hu, Eli Stavitski, Klaus Attenkofer, C. Petrovic
Abstract
We report ferromagnetism in 2H-Co 0.22 TaS 2 single crystals where Co atoms are intercalated in the van der Waals gap, and a systematic study of its magnetic critical behavior in the vicinity of T c 28 K. The obtained critical exponents = 0.43(2), = 1.15(1), and = 3.54(1) fulfill the Widom scaling relation = 1 + / and follow the scaling equation. This indicates that the spin coupling in 2H-Co 0.22 TaS 2 is of three-dimensional Heisenberg type coupled with long-range magnetic interaction, and that the exchange interaction decays with distance as J (r) r -4.69 . 2H-Co 0.22 TaS 2 exhibits a weak temperature-dependent metallic behavior in resistivity and negative values of thermopower with dominant electron-type carriers, in which obvious anomalies were observed below T c as well as the anomalous Hall effect (AHE). The linear scaling behavior between the modified anomalous Hall resistivity xy / 0 H and longitudinal resistivity 2 xx M/ 0 H implies that the origin of the AHE in 2H-Co 0.22 TaS 2 should be dominated by the extrinsic side-jump mechanism.