  Dispersion decomposes compound light into monochromatic components at
different spatial locations, which needs to be eliminated in imaging but
utilized in spectral detection. Metasurfaces provide a unique path to modulate
the dispersion only by adjusting the structural parameters without changing the
material as required for refractive elements. However, the common linear phase
compensation does not conform to the dispersion characteristics of the
meta-unit limiting dispersion modulation in broader wavelength bands, which is
desired for ultra-broadband or multiband imaging. Here, we propose a nonlinear
dispersive phase compensation method to design polarization-insensitive
achromatic metalenses from 400 nm to 1000 nm constructed with single-layer high
aspect ratio nanostructures. This band matches the response spectrum of a
typical CMOS sensor for both visible and near-infrared imaging applications
without additional lens replacement. Moreover, the capability of the method in
achieving arbitrary dispersion modulation is demonstrated for applications such
as chromatography imaging and spectral detection.
