Structural, magnetic, thermal, and electronic transport properties of single-crystal EuPd_2Sb_2

摘要

Single crystals of EuPd_2Sb_2 have been grown from PdSb self-flux. The properties of the single crystals have been investigated by x-ray diffraction, magnetic susceptibility X, magnetization M, electrical resistivity p, Hall coefficient R_H, and heat capacity C_p measurements versus temperature T and magnetic field H. Single-crystal x-ray diffraction studies confirmed that EuPd_2Sb_2 crystallizes in the tetragonal CaBe2Ge2-type structure. The X~(T) measurements suggest antiferromagnetic ordering at 6.0 K with the easy axis or plane in the crystallo-graphic ab plane. An additional transition occurs at 4.5 K that may be a spin reorientation transition. The C_p(T) data also show the two transitions at 6.1 and 4.4 K, respectively, indicating the bulk nature of the transitions. The 4.4 K transition is suppressed below 1.8 K while the 6.1 K transition moves down to 3.3 K in H=8 T. The p(T) data show metallic behavior down to 1.8 K along with an anomaly at 5.5 K in zero field. The anomaly is suppressed to 2.7 K in an 8 T field. The RH measurements indicated that the dominant charge carriers are electrons. The M(H) isotherms show three field-induced transitions at 2.75, 3.90, and 4.2 T magnetic fields parallel to the ab plane at 1.8 K. No transitions are observed in M(H) for fields parallel to the c axis.