Fig. 7

OAM beam mode purity. (a, b) Normalized intensity of the OAM beams with mode ‘\(l=+1\)’ and ‘\(l=-1\)’ in lower and higher band, respectively. (c, d) Normalized intensity of the OAM beams with mode ‘\(l=+1\)’ and ‘\(l=+2\)’ in lower and higher band, respectively. (e, f) Normalized intensity of the deflected OAM beams with mode ‘\(l=+1\)’ and ‘\(l=-1\)’ in lower and higher band, respectively.