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arXiv · 0806.2621

Spin freezing transition and non-Fermi-liquid self-energy in a 3-orbital model

Philipp Werner·Emanuel Gull·Matthias Troyer·Andrew J. Millis
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Abstract

A single-site dynamical mean field study of a three band model with the rotationally invariant interactions appropriate to the t_2g levels of a transition metal oxide reveals a quantum phase transition between a paramagnetic metallic phase and an incoherent metallic phase with frozen moments. The Mott transitions occurring at electron densities n=2,3 per site take place inside the frozen moment phase. The critical line separating the two phases is characterized by a self energy with the frequency dependence Σ(ω)\sim \sqrtω and a broad quantum critical regime. The findings are discussed in the context of the power law observed in the optical conductivity of SrRuO_3.

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Philipp Werner, Emanuel Gull, Matthias Troyer, Andrew J. Millis. 2008-10-27. Spin freezing transition and non-Fermi-liquid self-energy in a 3-orbital model. https://doi.org/10.1103/physrevlett.101.166405

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