Unconventional Superconductivity without quasiparticles in Strongly Correlated Metals

A correlated metal may completely lose quasiparticles when it is near a quantum critical point (QCP) [1]. It has been emphasized in the study of heavy fermion metals, where the low energy excitations are intrinsically fragile, under the notion of Kondo destruction [2]. How does the loss of quasiparticle influence the unconventional superconductivity remained to be a central question. Here [3], based on a cluster version of EDMFT approach, we demonstrate that unconventional superconductivity develops in the Anderson lattice model at the Kondo destruction critical points where the quasiparticles are completely lost. The transition temperature is exceptionally high compared to the effective Fermi temperature. Our results provide an understanding of unconventional superconductivity observed in the heavy fermion metals and are comparable with the experimental observations in the heavy fermion superconductors, for example CeCoIn5, where Tc reaches several percent of the effect Fermi temperature.





[1] S. Paschen & Q. Si, Nat. Rev. Phys. 3, 9 (2021).



[2] H. Hu, L. Chen, Q. Si, arXiv:2210.14183; Q. Si et al, Nature 413, 804 (2001



[3] H. Hu et al., arXiv:2109.13224