Emergence of localized magnetic moments near antiferromagnetic quantum criticality

Abstract

We revisit an antiferromagnetic quantum phase transition with $\mathbf{Q}=2{\mathbf{k}}_F$, where $\mathbf{Q}$ is an ordering wave vector and ${\mathbf{k}}_F$ is a Fermi momentum. Reformulating the Hertz-Moriya-Millis theory within the strong coupling approach to diagonalize the spin-fermion coupling term and performing the scaling analysis for an effective field theory with quantum corrections in the Eliashberg approximation, we propose a novel interacting fixed point for this antiferromagnetic quantum phase transition, where antiferromagnetic spin fluctuations become locally critical to interact with renormalized electrons. The emergence of local quantum criticality suggests a mechanism of $\omega /T$ scaling for antiferromagnetic quantum criticality, generally forbidden in the context of the Hertz-Moriya-Millis theory.

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References in corpus (5)

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