title: Kondo Destruction in RKKY-Coupled Kondo Lattice and Multi-Impurity Systems.
abstract: In a Kondo lattice, the spin exchange coupling between a local spin and the conduction electrons acquires nonlocal contributions due to conduction electron scattering from surrounding local spins and the subsequent RKKY interaction. It leads to a hitherto unrecognized interference of Kondo screening and the RKKY interaction beyond the Doniach scenario. We develop a renormalization group theory for the RKKY-modified Kondo vertex. The Kondo temperature T_{K}(y) is suppressed in a universal way, controlled by the dimensionless RKKY coupling parameter y. Complete spin screening ceases to exist beyond a critical RKKY strength y_{c} even in the absence of magnetic ordering. At this breakdown point, T_{K}(y) remains nonzero and is not defined for larger RKKY couplings y>y_{c}. The results are in quantitative agreement with STM spectroscopy experiments on tunable two-impurity Kondo systems. The possible implications for quantum critical scenarios in heavy-fermion systems are discussed.
authors.affiliation: Physikalisches Institut and Bethe Center for Theoretical Physics, Universität Bonn, Nussallee 12, D-53115 Bonn, Germany.
authors.forename: Ammar
authors.initials: A
authors.lastname: Nejati
authors.affiliation: Physikalisches Institut and Bethe Center for Theoretical Physics, Universität Bonn, Nussallee 12, D-53115 Bonn, Germany.
authors.forename: Katinka
authors.initials: K
authors.lastname: Ballmann
authors.affiliation: Physikalisches Institut and Bethe Center for Theoretical Physics, Universität Bonn, Nussallee 12, D-53115 Bonn, Germany.|Center for Correlated Matter, Zhejiang University, Hangzhou, Zhejiang 310058, China.
authors.forename: Johann
authors.initials: J
authors.lastname: Kroha