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arXiv · 1503.04007

Crossover from conventional to inverse indirect magnetic exchange in the depleted Anderson lattice

Maximilian W. Aulbach·Irakli Titvinidze·Michael Potthoff
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Abstract

We investigate the finite-temperature properties of an Anderson lattice with regularly depleted impurities. The physics of this model is ruled by two different magnetic exchange mechanisms: conventional Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction at weak hybridization strength V and a novel inverse indirect magnetic exchange (IIME) at strong V, both favoring a ferromagnetic ground state. The stability of ferromagnetic order against thermal fluctuations is systematically studied by static mean-field theory for an effective low-energy spin-only model emerging perturbatively in the strong-coupling limit as well as by dynamical mean-field theory for the full model. The Curie temperature is found at a maximum for a half-filled conduction band and at intermediate hybridization strengths in the crossover regime between RKKY and IIME.

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Maximilian W. Aulbach, Irakli Titvinidze, Michael Potthoff. 2015-05-19. Crossover from conventional to inverse indirect magnetic exchange in the depleted Anderson lattice. https://doi.org/10.1103/physrevb.91.174420

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