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arXiv · 1104.0364

Reaffirming the $d_{x^2-y^2}$ superconducting gap using the auto-correlation angle-resolved photoemission spectroscopy of Bi$_{1.5}$Pb$_{0.55}$Sr$_{1.6}$La$_{0.4}$CuO$_{6+δ}$

M. Hashimoto·R. -H. He·J. P. Testaud·W. Meevasana·R. G. Moore·D. H. Lu·Y. Yoshida·H. Eisaki·T. P. Devereaux·Z. Hussain·Z. -X. Shen
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Abstract

Knowledge of the gap function is important to understand the pairing mechanism for high-temperature ($T_\mathrm{c}$) superconductivity. However, Fourier transform scanning tunneling spectroscopy (FT STS) and angle-resolved photoemission spectroscopy (ARPES) in the cuprates have reported contradictory gap functions, with FT-STS results deviating strongly from a canonical $d_{x^2-y^2}$ form. By applying an "octet model" analysis to autocorrelation ARPES, we reveal that a contradiction occurs because the octet model does not consider the effects of matrix elements and the pseudogap. This reaffirms the canonical $d_{x^2-y^2}$ superconducting gap around the node, which can be directly determined from ARPES. Further, our study suggests that the FT-STS reported fluctuating superconductivity around the node at far above $T_\mathrm{c}$ is not necessary to explain the existence of the quasiparticle interference

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M. Hashimoto, R. -H. He, J. P. Testaud, W. Meevasana, R. G. Moore, D. H. Lu, Y. Yoshida, H. Eisaki, T. P. Devereaux, Z. Hussain, Z. -X. Shen. 2011-04-24. Reaffirming the $d_{x^2-y^2}$ superconducting gap using the auto-correlation angle-resolved photoemission spectroscopy of Bi$_{1.5}$Pb$_{0.55}$Sr$_{1.6}$La$_{0.4}$CuO$_{6+δ}$. https://doi.org/10.1103/physrevlett.106.167003

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