compared with cubic 
Abstract
We report low-temperature thermal-expansion measurements on single crystals of the layered heavy fermion system CeRhIn5−xSnx (0.3⩽x⩽0.6) and compare it with a previous study on the related cubic system CeIn3−xSnx (Küchler R. et al., Phys. Rev. Lett., 96 (2006) 256403). Both systems display a quantum critical point as proven by a divergent Grüneisen ratio. Most remarkably, the three-dimensional itinerant model explains quantum criticality in both systems, suggesting that the crystalline anisotropy in CeRhIn5−xSnx is unimportant. This is ascribed to the effect of weak disorder in these doped systems.