Fig. 2: Large-scale electronic structure.

a Typical STM topograph of a large flat region of the Fe₃Sn surface. Inset in (a) shows Fourier transform of a normalized dI/dV(r, V) map ((dI/dV)/(I/V)) for bias V = −150 mV. Atomic Bragg peaks related to the ab-plane lattice vectors are circled in red. b dI/dV linecut acquired over the vertical line denoted in the STM topograph in the inset. Blue arrow labeled as E₀ denotes an abrupt increase in conductance identified as a partial flat band in ref. ²⁸ c Radially averaged linecut generated from the FTs of normalized dI/dV(r, V) maps ((dI/dV)/(I/V)). E₀ denotes the energy below which the magnitude of the QPI wave vector is notably enhanced, concomitant with the increase in conductance in (b). Inset in c shows experimentally determined E₀ for two film thicknesses extracted from the equivalent radially averaged linecuts as shown in c. STM setup conditions: a I_set = 96 pA, V_sample = 12 mV; inset in a–c I_set = 1 nA, V_sample = 300 mV, V_exc = 5 mV.