Kondo Effects and Multipolar Order in the Cubic PrTr2Al20 (Tr=Ti, V)

Our single crystal study reveals that PrTr2Al20 (Tr = Ti and V) provides the examples of a cubic {\Γ}3 nonmagnetic ground doublet system that the Kondo effect including a -ln T dependent resistivity. The {\Γ}3 moments in PrV2Al20 induce anomalous metallic behavior through with conduction electrons, such as T1/2 dependent resistivity susceptibility below ~ 20 K down to its ordering temperature T_O = 0.6 K. PrTi2Al20, however, quadrupoles are well-localized and exhibit an order at_O = 2.0 K. Stronger Kondo coupling in PrV2Al20 than in PrTi2Al20 suppresses ordering, and instead promotes hybridization between the {\Γ}3 and conduction electrons, leading to most likely the quadrupolar Kondo.