Fig. 3: Wavefront engineering with h-SRRs.
From: All-optical active THz metasurfaces for ultrafast polarization switching and dynamic beam splitting
a Configurations of one supercell consisting of eight h-SRR unit cells for wavefront engineering. All the unit cells are designed with metal widths of 5 μm and periods p of 80 μm. The radii (rn) and gap splitting angles (αn) are tailored to obtain the relative phase response for unit cells #1 to #4 with r1 = 37, α1 = 10°; r2 = 34, α2 = 30°; r3 = 34, α3 = 80°; and r4 = 35, α4 = 110°. Unit cells #5 to #8 are identical to #1 to #4 but are rotated clockwise by 90°. b, c Simulated phase and amplitude spectra of cross-polarized component of each single h-SRR unit cell. d Simulated wavefront deflection of the cross-polarized component with plane wave incidence at different discrete frequencies ranging from 0.6 THz to 1.0 THz
