Metallic Lifshitz criticality in frustrated Kondo-lattices

Kondo lattices present a platform where itinerant electrons interact with a lattice of local moments [1]. When the interaction among the local moments is frustrated, novel physical phenomena may develop, as evidenced by recent experiments in CePdAl and Pr2Ir2O7 [2, 3]. Here, we study Kondo lattices with competing exchange-interactions among local moments, which frustrate their tendency towards magnetic orderings and drives quantum phase transitions between distinct magnetically ordered phases. We view such frustration-driven transitions as quantum Lifshitz transitions in the local-moment sector, and show that the coupling between the itinerant electrons and the local moments is strongly enhanced at the associated quantum critical point. The resultant strong scatterings between the itinerant electrons and magnetic fluctuations tend to decohere the quasiparticles in the metal, and promotes non-Fermi liquid behaviors. Thus, our results shed new light on the global phase diagram of the heavy fermion systems and, especially, the behavior of frustrated Kondo lattice.



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[2] H. Zhao et al, Nat. Phys. 15, 1261 (2019).

[3] M. Kavai et al, Nat Commun 12, 1377 (2021).