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arXiv · 1402.2215

Angle-resolved photoemission spectroscopy study of HgBa$_{2}$CuO$_{4+\delta}$

I. M. Vishik·N. Barišić·M. K. Chan·Y. Li·D. D. Xia·G. Yu·X. Zhao·W. S. Lee·W. Meevasana·T. P. Devereaux·M. Greven·Z. -X. Shen
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Abstract

HgBa$_{2}$CuO$_{4+\delta}$ (Hg1201) has been shown to be a model cuprate for scattering, optical, and transport experiments, but angle-resolved photoemission spectroscopy (ARPES) data are still lacking owing to the absence of a charge-neutral cleavage plane. We report on progress in achieving the experimental conditions for which quasiparticles can be observed in the near-nodal region of the Fermi surface. The d-wave superconducting gap is measured and found to have a maximum of 39 meV. At low temperature, a kink is detected in the nodal dispersion at approximately 51 meV below the Fermi level, an energy that is different from other cuprates with comparable T$_c$. The superconducting gap, Fermi surface, and nodal band renormalization measured here provide a crucial momentum-space complement to other experimental probes.

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I. M. Vishik, N. Barišić, M. K. Chan, Y. Li, D. D. Xia, G. Yu, X. Zhao, W. S. Lee, W. Meevasana, T. P. Devereaux, M. Greven, Z. -X. Shen. 2014-02-10. Angle-resolved photoemission spectroscopy study of HgBa$_{2}$CuO$_{4+\delta}$. https://doi.org/10.1103/physrevb.89.195141

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