Fig. 3: Measurement of the projected bulk dispersion of the maximally charged Weyl point (WP).

a Photograph of the fabricated 3D photonic crystal, consisting of 17 × 17 × 10 unit cells. b Experimental setup. The field pattern is measured on (001) surface of the sample. Green and blue arrows represent the source and probe, respectively. c Measured projected bulk dispersion along the high-symmetry line \(\bar{\Gamma }-\bar{{{{{{\rm{{X}}}}}}}}-\bar{{{{{{\rm{M}}}}}}}-\bar{\Gamma }\). Grey curves display the numerically-calculated projected bulk dispersion. Red (green) dots represent the projections of the maximally charged WP (charge-2 WP). The colourmap measures the energy density.