Thermodynamics of localized magnetic moments in a Dirac conductor

V. Cheianov; M. Szyniszewski; E. Burovski; Yu. Sherkunov; V. Fal'ko

doi:10.1103/physrevb.86.054424

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arXiv · 1112.4096

Thermodynamics of localized magnetic moments in a Dirac conductor

V. Cheianov·M. Szyniszewski·E. Burovski·Yu. Sherkunov·V. Fal'ko

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Abstract

We show that the magnetic susceptibility of a dilute ensemble of magnetic impurities in a conductor with a relativistic electronic spectrum is non-analytic in the inverse tempertature at $1/T\to 0$. We derive a general theory of this effect and construct the high-temperature expansion for the disorder averaged susceptibility to any order, convergent at all tempertaures down to a possible ordering transition. When applied to Ising impurities on a surface of a topological insulator, the proposed general theory agrees with Monte Carlo simulations, and it allows us to find the critical temperature of the ferromagnetic phase transition.

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BibTeX RIS

V. Cheianov, M. Szyniszewski, E. Burovski, Yu. Sherkunov, V. Fal'ko. 2011-12-17. Thermodynamics of localized magnetic moments in a Dirac conductor. https://doi.org/10.1103/physrevb.86.054424

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