Two-Dimensional Optical Metasurfaces: From Plasmons to Dielectrics

Figure 13

Example of a DGMOE: An axicon constructed from Si nanoantennas. (a) Schematic of a conventional glass axicon focusing light into a Bessel beam. (b) Schematic of a DGMOE axicon featuring an ultrathin patterned layer of silicon on a quartz substrate. (c) Transversal distribution of Bessel beam generated by the DGMOE. (d) SEM image of the fabricated DGMOE. (e) Measured intensity profile of the non-diffractive Bessel beam generated behind the DGMOE in the x and z plane. The intensity (I) along the center of Bessel beam is plotted in the inset along the z axis. The inset along the x axis shows the cross-sectional intensity profile at the z = 0 plane. a.u., arbitrary units [25].

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