Kondo Destroys Nesting in the 5$f$ Tritelluride UTe$_3$

In the rare-earth tritellurides (RTe$_3$), localized 4$f$ moments order antiferromagnetically, while itinerant conduction electrons form highly nested Fermi surfaces that give rise to charge density wave (CDW) order. Increasing the coupling between these localized and itinerant electrons could drive the system into the Kondo regime, where the fate of the nested Fermi surface and resulting electronic structure remains unknown. However, across the rare-earth series this coupling remains weak, and a heavy Fermi surface does not emerge. Here, we show that the 5$f$ tritelluride $\beta$-UTe$_3$~ enters the Kondo regime, where the nested Fermi surface is destroyed and reconstructed into heavy quasiparticle bands. The Kondo state is confirmed by scanning tunneling microscopy measurements, that reveal Fano line shapes in the differential conductance characteristic of Kondo materials. Furthermore, quasiparticle interference imaging reveals that the bands lose their nesting as they approach the Fermi level and reconstruct into heavy quasiparticle bands. A tight-binding model incorporating Kondo hybridization reproduces the QPI features and demonstrates that the characteristic nesting of the rare-earth tritellurides is destroyed at the Fermi surface. The destruction of the nested Fermi surface is speculated to explain the absence of a CDW in our topographic imaging and may shed light on the unconventional ferromagnetism recently reported in this material.