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arXiv · 0806.3502

Spin-resolved impurity resonance states in electron-doped cuprate superconductors

Bin Liu
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Abstract

With the aim at understanding the non-monotonic $d_{x^{2}-y^{2}}$-wave gap, we analyze the local electronic structure near impurities in the electron-doped cuprate superconductors. We find that the local density of states near a non-magnetic impurity in the scenario of $d_{x^{2}-y^{2}}$-wave superconductivity with higher harmonics is qualitatively different from that obtained from the $d_{x^{2}-y^{2}}$-wave superconductivity coexisting with antiferromagnetic spin density wave order. We propose that spin-polarized scanning tunneling microscopy measurements can distinguish the two scenarios and shed light on the real physical origin of a non-monotonic $d_{x^{2}-y^{2}}$-wave gap.

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Bin Liu. 2009-04-23. Spin-resolved impurity resonance states in electron-doped cuprate superconductors. https://doi.org/10.1103/physrevb.79.172501

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