Suppression of quadrupolar order on Si doping in YbRu2(Ge1-xSix)2

We have investigated the magnetic properties of polycrystalline YbRu2(Ge1-xSix)(2) samples using magnetic susceptibility, electrical resistivity, and specific heat measurements. All the results indicate that the Yb ions in YbRu2(Ge1-xSix)(2) are in a stable trivalent state. The antiferromagnetic ordering shifts to lower temperature with increasing Si concentration (x). The weak Kondo-like resistivity minimum observed in the resistivity data for x = 0 shifts toward lower temperature with an increase in the Si content and finally disappears. The most dramatic observation is the complete suppression of the quadrupolar ordering in YbRu2Ge2 (T-Q = 10 K) even for 2% Si doping.