Low-dispersion Metasurfaces for Wideband Gradient-index (GRIN) Media up to Ka-band

This paper introduces and characterizes square, interdigitated square and hexagon low-dispersion metasurfaces obeying standard PCB fabrication rules and suitable for wideband GRIN media. They are compared over refractive index range, anisotropy and power handling. Results show that all proposed unit-cells have low dispersion suitable for designs across the Ka-band. The interdigitated square cell exhibits the largest index range (1.22–2.416) while the hexagonal unit-cell has the highest power handling (136MW/m
²
) and lowest anisotropy (6% index variation) but reduced index range (1.22–2.098).