Figure 1

Sample characterisation. (a) X-ray diffraction patterns at room temperature for the Au₂Pb samples. The major diffraction peaks can be indexed with a cubic Laves phase of Au₂Pb. A few tiny diffraction peaks are from the impurity phases of a small amount of Pb residue. Inset: the X-ray diffraction pattern from the basal plane crystal surface of Au₂Pb only shows (111)_n reflections, which indicates the measured crystal plane of the crystal is (111) plane. (b) High-resolution transmission electron microscopy image of Au₂Pb crystal. (c) Selected area electron diffraction image looking down from the zone axis showing the reciprocal lattice of Au₂Pb.