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arXiv · 0704.1815

Kondo-lattice screening in a d-wave superconductor

Daniel E. Sheehy·Joerg Schmalian
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Abstract

We show that local moment screening in a Kondo lattice with d-wave superconducting conduction electrons is qualitatively different from the corresponding single Kondo impurity case. Despite the conduction-electron pseudogap, Kondo-lattice screening is stable if the gap amplitude obeys $Δ<\sqrt{\tk D}$, in contrast to the single impurity condition $Δ<\tk$ (where $\tk$ is the Kondo temperature for $Δ= 0$ and D is the bandwidth). Our theory explains the heavy electron behavior in the d-wave superconductor Nd_{2-x}Ce_{x}CuO_{4}.

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Daniel E. Sheehy, Joerg Schmalian. 2008-01-31. Kondo-lattice screening in a d-wave superconductor. https://doi.org/10.1103/physrevb.77.125129

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