Non-Fermi-liquid behavior and superconducting fluctuations caused by hybridization

The exact solution is proposed that describes the low-energy properties of conduction electrons hybridized with localized 5f electrons. For small concentrations of the latter, the solution for 5f orbitals manifests a mixed valence and crossover from a Fermi-liquid-like behavior at very low energies to the two-channel non-Fermi-liquid behavior at higher energies. For the finite concentration of localized electrons the same hybridization dynamically yields an attraction between conduction electrons, resulting in superconducting fluctuations (Cooper-like pairs) present in the low-temperature phase. We predict a quantum transition to the phase, in which superconducting fluctuations coexist with magnetic ones. Possible relevance of our results to the data of experiments in some U-based compounds is discussed.