Figure 4.

(a–d) Normalized intensity profiles of the focal spot of the hybrid metalens at $x-z$ plane ($y=0$) for ${\lambda }_d=260$ nm and 380 nm under both LCP/RCP illuminations respectively. (e–h) Normalized intensity profiles of the focal spot of the hybrid metalens at $x-y$ plane ($z=f$) at ${\lambda }_d=260$ nm and 380 nm under LCP, RCP illumination respectively. (i,k) depicts the intensity profile at the corresponding horizontal dashed lines shown at (e–h), at $y=0$, giving similar FWHM values under both LCP and RCP polarization. (j,l) shows the intensity profile at the corresponding vertical dashed lines shown at (a–d), at $x=0$. All the designed metalenses have the same diameter of $20\mathrm{\mu }$m and NA$\approx 0.8$.