Double Exchange model for nanoscopic clusters

Abstract

We solve the double exchange model on nanoscopic clusters exactly, and specifically consider a six-site benzene-like nanocluster. This simple model is an ideal testbed for studying magnetism in nanoclusters and for validating approximations such as the dynamical mean field theory (DMFT). Non-local correlations arise between neighboring localized spins due to the Hund's rule coupling, favoring a short-range magnetic order of ferro- or antiferromagnetic type. For a geometry with more neighboring sites or a sufficiently strong hybridization between leads and the nanocluster, these non-local correlations are less relevant, and DMFT can be applied reliably.

9 pages, 9 figures, 1 table

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Cited by in corpus (3)

• Dynamical vertex approximation in its parquet implementation: application to Hubbard nano-rings
• Realistic theory of electronic correlations in nanoscopic systems
• Tunable site- and orbital-selective Mott transition and quantum confinement effects in La${}_{0.5}$Ca${}_{0.5}$MnO${}_3$ nanoclusters