Nanostructured gradient-index antireflection diffractive optics.

  title={Nanostructured gradient-index antireflection diffractive optics.},
  author={Chih-Hao Chang and J. A. Dom{\'i}nguez-Caballero and H. Choi and G. Barbastathis},
  journal={Optics letters},
  volume={36 12},
We describe the fabrication and characterization of a nanostructured diffractive element with near-zero reflection losses. In this element, subwavelength nanostructures emulating adiabatic index matching are integrated on the surface of a diffractive microstructure to suppress reflected diffraction orders. The fabricated silicon grating exhibits reflected efficiencies that are suppressed by 2 orders of magnitude over broad wavelength bands and wide incident angles. Theoretical models of the… Expand
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