arXiv 1503.040072015-03cond-mat.str-elcond-mat.quant-gas

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

Maximilian W. Aulbach, Irakli Titvinidze, Michael Potthoff

备注：: 12 pages, 11 figures, v2 with minor corrections
发表信息：: Phys. Rev. B 91, 174420 (2015)
DOI：: 10.1103/PhysRevB.91.174420

英文摘要：

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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