Figure 1.

(a, b) Side and top views of the atomic structure of AuSn₄. Yellow and gray balls denote Au and Sn atoms, respectively. (c) XPS survey spectrum of as-cleaved AuSn₄. (d) XRD spectrum for a single crystal of AuSn₄. The inset shows a photograph of grown single crystals. (e) Bulk electronic structure of AuSn₄ obtained by density functional theory. Bands were obtained by projecting the available k_z within the whole Brillouin zone. (f) The corresponding ARPES data are shown as a sum of in-plane and out-of-plane light polarization, with photons of 48 eV. At this energy, it is possible to access the full Brillouin zone along Γ-X, along the orange line of the inset, and the photoemission matrix elements are favorable. The overall agreement between the calculated and the measured energy-momentum dispersion is evident.