  Manipulating the polarization of light on the microscale or nanoscale is
essential for integrated photonics and quantum optical devices. Nowadays, the
metasurface allows one to build on-chip devices that efficiently manipulate the
polarization states. However, it remains challenging to generate different
types of polarization states simultaneously, which is required to encode
information for quantum computing and quantum cryptography applications. By
introducing geometrical-scaling-induced (GSI) phase modulations, we demonstrate
that an assembly of circularly polarized (CP) and linearly polarized (LP)
states can be simultaneously generated by a single metasurface made of L-shaped
resonators with different geometrical features. Upon illumination, each
resonator diffracts the CP state with a certain GSI phase. The interaction of
these diffractions leads to the desired output beams, where the polarization
state and the propagation direction can be accurately tuned by selecting the
geometrical shape, size, and spatial sequence of each resonator in the unit
cell. As an example of potential applications, we show that an image can be
encoded with different polarization profiles at different diffraction orders
and decoded with a polarization analyzer. This approach resolves a challenging
problem in integrated optics and is inspiring for on-chip quantum information
processing.
