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Co-operative Two-Channel Kondo Effect

N. Andrei·P. Coleman·H. Y. Kee·A. M. Tsvelik
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Abstract

We discuss how the properties of a single-channel Kondo lattice model are modified by additional screening channels. Contrary to current wisdom, additional screening channels appear to constitute a relevant perturbation which destabilizes the Fermi liquid. When a heavy Fermi surface develops, it generates zero modes for Kondo singlets to fluctuate between screening channels of different symmetry, producing a divergent composite pair susceptibility. Additional screening channels couple to these divergent fluctuations, promoting an instability into a state with long-range composite order.

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N. Andrei, P. Coleman, H. Y. Kee, A. M. Tsvelik. 1997-07-01. Co-operative Two-Channel Kondo Effect. https://doi.org/10.1088/0953-8984%2F10%2F15%2F002

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