Reconstruction-induced trefoil knot Fermi contour of Au(111)

TL;DR

This study uses ARPES to reveal how the herringbone reconstruction of Au(111) causes a trefoil knot-shaped Fermi surface, resolving previous discrepancies between microscopy and photoemission results.

Contribution

It demonstrates that the uniaxial lattice distortion from the reconstruction significantly alters the surface state dispersion, creating a trefoil knot-shaped Fermi surface.

Findings

Reconstruction induces a trefoil knot-shaped Fermi surface.

Surface state dispersion varies around reciprocal lattice points.

Results reconcile previous microscopy and photoemission discrepancies.

Abstract

Using angle-resolved photoemission spectroscopy (ARPES), we study the effect of the so-called herringbone reconstruction of Au(111) on the dispersion of the free electron-like surface state. While earlier ARPES investigations have only reported a minor interplay of the surface state dispersion and the underlying reconstruction, we show that the uniaxial lattice distortion and the thereby changed reciprocal lattice for the first atomic layer leads to distinct surface state dispersions around the first order reciprocal lattice points of the three domains, creating a constant energy surface resembling a trefoil knot. The findings resolve the long-standing discrepancy between, on one hand, the reconstruction-induced surface state modifications reported in scanning tunnelling microscopy and first principle calculations and, on the other hand, their conspicuous absence in photoemission.