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arXiv · 1403.2631

Superconductivity from spoiling magnetism in the Kondo lattice model

Mohammad Zhian Asadzadeh·Michele Fabrizio·Federico Becca
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Abstract

We find evidence that superconductivity intrudes into the paramagnetic-to-magnetic transition of the Kondo lattice model if magnetic frustration is added. Specifically, we study by variational method the model on a square lattice in the presence of both nearest- ($t$) and next-nearest-neighbor ($t^\prime$) hopping of the conduction electrons. We find that when $t^\prime/t$ is finite a $d$-wave superconducting dome emerges between the magnetic and paramagnetic metal phases and close to the compensated regime, i.e., the number of conduction electrons equal to the number of localized spin-1/2 moments. Superconductivity is further strengthened by a direct antiferromagnetic exchange between the localized moments, to such an extent that we even observe coexistence with magnetic order.

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Mohammad Zhian Asadzadeh, Michele Fabrizio, Federico Becca. 2014-03-11. Superconductivity from spoiling magnetism in the Kondo lattice model. https://arxiv.org/abs/1403.2631

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