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Superconducting Gap Anisotropy in Nd$_{1.85}$Ce$_{0.15}$CuO$_4$: Results from Photoemission

N. P. Armitage·D. H. Lu·D. L. Feng·C. Kim·A. Damascelli·K. M. Shen·F. Ronning·Y. Onose·Y. Taguchi·Y. Tokura·Z. -X. Shen
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Abstract

We have performed angle resolved photoelectron spectroscopy on the electron doped cuprate superconductor Nd$_{1.85}$Ce$_{0.15}$CuO$_4$. A comparison of the leading edge midpoints between the superconducting and normal states reveals a small, but finite shift of 1.5-2 meV near the ($π$,0) position, but no observable shift along the zone diagonal near ($π$/2,$π$/2). This is interpreted as evidence for an anisotropic superconducting gap in the electron doped materials, which is consistent with the presence of d-wave superconducting order in this cuprate superconductor.

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N. P. Armitage, D. H. Lu, D. L. Feng, C. Kim, A. Damascelli, K. M. Shen, F. Ronning, Y. Onose, Y. Taguchi, Y. Tokura, Z. -X. Shen. 2000-12-01. Superconducting Gap Anisotropy in Nd$_{1.85}$Ce$_{0.15}$CuO$_4$: Results from Photoemission. https://doi.org/10.1103/physrevlett.86.1126

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