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Flow equation approach to heavy fermion systems

Karsten Meyer
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Abstract

We use Wegner's flow equation method to investigate the infinite-$U$ periodic Anderson model. We show that this method poses a new approach to the description of heavy fermion behaviour. Within this scheme we derive an effective Hamiltonian where the $c$ and $f$ degrees of freedom are decoupled. By evaluating one-particle energies as well as correlation functions we find an electronic structure which comprises two gapped quasiparticle bands. We also address the lattice Kondo temperature, which shows a typical exponential dependence on the hybridisation energy. This energy scale exhibits a significant decrease compared to that of the single impurity Anderson model.

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Karsten Meyer. 2004-11-30. Flow equation approach to heavy fermion systems. https://doi.org/10.1140/epjb%2Fe2004-00354-y

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