Crystal Field Wave Functions Of Cexla1-Xrhin5

We have measured dc magnetization M(H) of CexLa1-xRhIn5 (x = 0.03, 0.05, and 0.1) to study a crystalline electric field (CEF) effect. We report that M(H) is isotropic at low temperatures in contrast to Ising like anisotropy in CeRhIn5, yielding ground state wave functions similar to those of the parent compound CeIn3. We also show that M(H) of x = 0.03, which exhibits the smallest intersite interactions, can be explained solely by the CEF effect, without taking into account the Kondo effect.