Extended Data Fig. 3: Inverse Fast Fourier Transform (iFFT) analysis of valley polarization.
From: Visualizing interaction-driven restructuring of quantum Hall edge states
a, Fourier filter for retaining only the Bragg peaks in the FFT data. b-e, Representative examples of iFFT generated real-space intensity maps, for a strongly valley polarized state (Z ~ 1, b); graphene lattice (Z = 0, c); left (d) and right (e) panels in Fig. 3b. Partial valley polarization is visible in d,e as larger iFFT amplitude on one sublattices. Yellow hexagons denote expected graphene atomic positions. Weaker contrast near the boundaries of b-e is a result of the Blackman window function applied to obtain the FFT peaks.
