Thermal expansion and magnetostriction studies of a Kondo lattice compound: CeAgSb2

We have investigated a single crystal of CeAgSb2 using low field ac-susceptibility, thermal expansion and magnetostriction measurements. The thermal expansion coefficient a, exhibits highly anisotropic behaviour between 3 K and 80 K: alpha (for DeltaL/L) perpendicular to c exhibits a sharp peak at T-N followed by a broad maximum at 20 K, while a sharp negative peak at TN followed by a minimum at 20 K has been observed for (DeltaL/L parallel to) the c direction. The observed maximum and minimum in alpha(T) at 20 K have been attributed to the crystalline field effect (CEF). The magnetostriction (MS) also exhibits anisotropic behaviour with a large MS along the c-axis.