Extended Data Fig. 2: Additional linear and complex topological-spectral correlations.
From: Broadband control of topological–spectral correlations in space–time beams
a, Linear correlation with OAM spanning from ℓ = 10 to 30 corresponding to a helical wave packet with small orbital radius. b, Three intertwined helices obtained by employing discrete steps with δℓ = 3 in the correlation. c, Parabolic correlation with broadband OAM content spanning from ℓ = 5 to 90. d, Sinusoidal correlation completing two full oscillations over the spectral bandwidth. Due to the symmetry of the sinusoidal function, the reconstructed intensity does not show oscillations, analogously to the achiral wave packet obtained from parabolic correlations in Fig. 4d. Each panel shows the intensity of the electric field at t = 0 (top left), the time-averaged color image of the beam obtained by an hyperspectral camera (bottom left), the iso-surface at 10% of the intensity peak (center), and the experimental correlation (right). The size of the intensity and color images is 4 mm.
