Metasurface-based optical signal manipulation devices for optical fiber communications

1 . An apparatus comprising:

a fiber input, the fiber input comprising a plurality of input fiber cores, the plurality of input fiber cores receiving a plurality of input optical signals;

an optical signal manipulation device, the optical signal manipulation device comprising:

an input aperture held in spaced relation to the fiber input to receive the plurality of input optical signals in a first spatial arrangement;

a plurality of metasurfaces, each of the plurality of metasurfaces comprising a plurality of nanostructures separated from one another by less than a wavelength of the plurality of input optical signals; and

an output aperture, wherein the plurality of metasurfaces manipulate phase profiles of the plurality of input optical signals to generate a plurality of output optical signals, wherein the plurality of output optical signals have a second spatial arrangement at the output aperture that differs from the first spatial arrangement; and

a fiber output comprising a plurality of output fiber cores, wherein the fiber output is held in spaced relation to the output aperture of the optical signal manipulation device such that the plurality of output fiber cores receive the plurality of output optical signals in the second spatial arrangement, wherein the optical signal manipulation device comprises one of a fiber mode shuffler, a fiber coupler, a power splitter, or a 90-degree optical hybrid,

wherein at least two metasurfaces are disposed on opposite surfaces of a shared transmissive substrate, and wherein the at least two metasurfaces are configured to modify wavefront tilts of the plurality of input optical signals in a shared propagation direction toward the output aperture of the optical signal manipulation device.

2 . The apparatus of claim 1 , wherein the fiber input comprises a first multicore fiber and the plurality of input fiber cores are disposed in a common cladding of the first multicore fiber.

3 . The apparatus of claim 2 , wherein the plurality of input fiber cores are disposed in the common cladding in an arrangement that corresponds to the first spatial arrangement of the plurality of input optical signals.

4 . The apparatus of claim 3 , wherein the fiber output comprises a second multicore fiber and the plurality of output fiber cores are disposed in a common cladding of the second multicore fiber in an arrangement that corresponds to the second spatial arrangement of the plurality of output optical signals.

5 . The apparatus of claim 1 , wherein the fiber input comprises a first single core fiber array and the fiber output comprises a second single core fiber array.

6 . The apparatus of claim 5 , wherein the first and second single core fiber arrays comprise the same core spacing.

7 . The apparatus of claim 1 , wherein the plurality of metasurfaces comprises a first metasurface and a second metasurface, the first metasurface comprising a first plurality of nanostructures arranged in a pattern based on the first spatial arrangement such that the first plurality of nanostructures modify wavefront tilts of the plurality of input optical signals between the first metasurface and the second metasurface.

8 . The apparatus of claim 7 , wherein the second metasurface re-directs the plurality of output optical signals towards the plurality of output fiber cores in the second spatial arrangement.