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arXiv · 1009.0860

Crossover in the two-impurity Kondo model induced by direct charge tunneling

Justin Malecki·Eran Sela·Ian Affleck
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Abstract

Quantum critical behavior in the two-impurity Kondo model requires the distinct separation of two scales, T_K >> T*, where T_K is the Kondo temperature and T* is the scale at which the system renormalizes away from the quantum critical point to a stable Fermi liquid fixed point. We provide a derivation of T* based on the renormalization group to lowest order. This result is confirmed by a numerical renormalization group (NRG) analysis which supplements the analytic derivation with additional quantitative precision. The form of the low-energy Fermi liquid fixed point is derived and subsequently confirmed by the NRG. We discuss implications for series double quantum dot systems.

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Justin Malecki, Eran Sela, Ian Affleck. 2011-10-31. Crossover in the two-impurity Kondo model induced by direct charge tunneling. https://doi.org/10.1103/physrevb.82.205327

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