Anisotropic behavior in resistivity of RAgSb 2 ( R=Ce, La )

Abstract

CeAgSb 2 crystallizes in the tetragonal ZrCuSi 2 type structure (P4/nmm), which consists of Sb–Ce, Sb–Ag–Ce, Sb–Sb layers. It shows the peculiar anisotropic ferromagnetic ordering below 9.7 K with a small ordered moment of 0.33 μ B. Its residual resistivity steeply increases above p c ≅ 3.3 GPa where the magnetic order disappears. It is expected that the p–f mixing on the peculiar hollow square pillar-like Fermi surface plays an important role in CeAgSb 2, while similar Fermi surfaces were not observed in LaAgSb 2 . We have measured the anisotropy in the electrical resistivity of Ce x La 1− x AgSb 2 to study the p–f mixing effect. Small humps were observed in the temperature dependence of the resistivity in Ce x La 1− x AgSb 2. We expected them the CDW transition. The CDW state coexisted with the ferromagnetic state around x = 0.2 .