THE QUADRUPOLAR KONDO EFFECT - A NEW MECHANISM FOR HEAVY ELECTRONS

An explicit mapping between an Anderson model for a non-Kramers uranium (U) ion in a cubic metallic host to a two-channel pseudo-spin Kondo model is demonstrated. Thus the heavy electron behavior of UBe13 may arise from a pure electric quadrupole Kondo effect. The origin of small characteristic temperatures despite relatively conduction-f mixing is clarified. In addition to UBe13, other candidate materials (including PrPb3, UPt4Au and Tb in Th) which might exhibit this effect are discussed. A critical review is given of experiments which suggest to the contrary that there is a low lying Kramers' doublet in UBe13.