Destructive hybridization interference and Kondo breakdown in multi orbital Anderson lattices

In a recent publication https://journals.aps.org/prb/pdf/10.1103/PhysRevB.102.205132 we demonstrated that strongly correlated multi impurity problems can be grouped into two fundamentally different classes, depending on the Kondo screening mechanism.

Here we use DMFT+NRG in order to study the impact of these findings in the multi orbital extension of the periodic Anderson model. Whereas the hybridization of a single correlated orbital with two distinct conduction bands always adds up constructively, $T_ ext{K}propto exp(-alpha U/(Gamma_1+Gamma_2))$, we show that this does not have to be the case in lattice models, where, in remarkable contrast, also $T_ ext{K}propto exp(-alpha U/(Gamma_1-Gamma_2))$ is possible.

At high symmetry points, despite having an intact Fermi surface, the Kondo effect breaks down, resulting in an asymptotically scale-invariant (i.e., power-law) spectrum of the correlated orbitals $propto|omega|^r$ with universal exponent $rapprox 0.30$. This orbital selective Mott phase demonstrates the possibility of metallic local criticality within the general framework of ordinary DMFT. If magnetism is included, this critical point is hidden below an extended region of metallic ferromagnetism