Systematic study of anisotropic transport and magnetic properties of RAgSb2 (R = Y, La-Nd, Sm, Gd-Tm)

Anisotropic measurements of the magnetic and transport properties have been performed on high-quality single crystals of the RAgSb2 series of compound s with R = Y, La-Nd, Sm, Gd-Tm. For most of these compounds, strong magneti c anisotropies, created by crystalline electric field (CEF) splitting of th e Hund's rule ground state, confine the moments to the basal plane. Additio nal anisotropy within the basal plane is also observed in DyAgSb2, leading to a series of metamagnetic transitions. All of the compounds order antifer romagnetically at low temperatures except for the nonmagnetic compounds LaA gSb2 and YAgSb2 and the ferromagnetic compound CeAgSb2. For R = Y, La-Nd, a nd Sm clear de Haas-van Alphen oscillations in fields as low as 30 kOe and at temperatures as high as 25 K can be measured. Throughout the series, the low-temperature transverse magnetoresistance is large [Delta rho(H)/rho(0) approximate to 60 in SmAgSb2 at 55 kOe] and deviates strongly from quadrati c behavior with field the dependence of Delta rho(H)/rho(0) ranging between H-0.8 and H-1.5. (C) 1999 Elsevier Science B.V. All rights reserved.