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arXiv · 1410.2406

Generation of localized magnetic moments in the charge-density-wave state

R. S. Akzyanov·A. V. Rozhkov
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Abstract

We propose a mechanism explaining the generation of localized magnetic moments in charge-density-wave compounds. Our model Hamiltonian describes an Anderson impurity placed in a host material exhibiting the charge-density wave. There is a region of the model's parameter space, where even weak Coulomb repulsion on the impurity site is able to localize the magnetic moment on the impurity. The phase diagram of a single impurity at T=0 is mapped. To establish the connection with experiment thermodynamic properties of a random impurity ensemble is studied. Magnetic susceptibility of the ensemble diverges at low temperature; heat capacity as a function of the magnetic field demonstrates pronounced low field peak. Both features are consistent with experiments on orthorhombic TaS3 and blue bronze.

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R. S. Akzyanov, A. V. Rozhkov. 2014-10-09. Generation of localized magnetic moments in the charge-density-wave state. https://doi.org/10.1140/epjb%2Fe2015-60219-x

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