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arXiv · 1408.6447

Local Kondo temperatures in atomic chains

Ricardo Agundez·Joe Salfi·Sven Rogge·Miriam Blaauboer
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Abstract

We study the effect of disorder in strongly interacting small atomic chains. Using the Kotliar- Ruckenstein slave-boson approach we diagonalize the Hamiltonian via scattering matrix theory. We numerically solve the Kondo transmission and the slave-boson parameters that allow us to calculate the Kondo temperature. We demonstrate that in the weak disorder regime, disorder in the energy levels of the dopants induces a non-screened disorder in the Kondo couplings of the atoms. We show that disorder increases the Kondo temperature of a perfect chain. We find that this disorder in the couplings comes from a local distribution of Kondo temperatures along the chain. We propose two experimental setups where the impact of local Kondo temperatures can be observed.

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Ricardo Agundez, Joe Salfi, Sven Rogge, Miriam Blaauboer. 2014-08-27. Local Kondo temperatures in atomic chains. https://doi.org/10.1103/physrevb.91.041117

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