  In this paper, we realize the concept of analog computing using an array of
engineered gradient dielectric meta-reflect-array. The proposed configuration
consists of individual subwavelength silicon nanobricks in combination with
fused silica spacer and silver ground plane realizing a reflection beam with
full phase coverage $2\pi$ degrees as well as amplitude range $0$ to $1$.
Spectrally overlapping electric and magnetic dipole resonances, such high-index
dielectric metasurfaces can locally and independently manipulate the amplitude
and phase of the incident electromagnetic wave. This practically feasible
structure overcomes substantial limitations imposed by plasmonic metasurfaces
such as absorption losses and low polarization conversion efficiency in the
visible range. Using such CMOS-compatible and easily integrable platforms
promises highly efficient ultrathin planar wave-based computing systems which
circumvent the drawbacks of conventional bulky lens-based signal processors.
Based on these key properties and general concept of spatial Fourier
transformation, we design and realize broadband mathematical operators such as
differentiator and integrator in the telecommunication wavelengths.
