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

TL;DR

This study advances ARPES measurements on HgBa$_{2}$CuO$_{4+\delta}$, revealing a d-wave superconducting gap and a unique nodal dispersion kink, providing key insights into its electronic structure.

Contribution

It demonstrates the feasibility of ARPES on Hg1201 and reports detailed measurements of the superconducting gap and nodal band renormalization.

Findings

Superconducting gap maximum of 39 meV

Detection of a 51 meV kink in nodal dispersion

Provides momentum-space data complementing other experiments

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.