studied by Angle-Resolved Photoemission Spectroscopy*

We investigate the electronic structure of PtPb₄ by using ultrahigh resolution, laser based Angle Resolved Photoemission Spectroscopy(ARPES) and Density functional theory(DFT) calculations. This material is a compound related to PtSn₄, which exhibits exotic topological properties such as Dirac node arcs. The Fermi surface(FS) of PtPb₄ has at least two electron pockets at the center of the Brillouin zone(BZ) and several hole pockets around the zone boundaries. Although the crystal structure has 4-fold symmetry, the ARPES data reveals a FS with only 2-fold symmetry, showing a rectangular FS sheet around X points and two intersected circular FS sheet around Y points. X-ray scattering data points to the stacking order as a key factor for the breaking of the 4-fold symmetry observed in ARPES data. The experimental results are in a reasonable agreement with the DFT calculations.