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Enhanced pairing in doped quantum magnets with frustrating hole motion

Didier Poilblanc
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Abstract

Evidence for strong pairing at arbitrary small J/t is provided in a t-J model on the checkerboard lattice for the sign of hopping leading to frustration in hole motion. Destructive quantum interferences suppress Nagaoka ferromagnetism when J->0 and reduce drastically coherent hole motion in the fluctuating singlet background. It is shown that, by pairing in various orbital symmetry channels, holes can benefit from a large gain of kinetic energy.

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Didier Poilblanc. 2004-07-10. Enhanced pairing in doped quantum magnets with frustrating hole motion. https://doi.org/10.1103/physrevlett.93.197204

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