Metamaterials comprising assemblies of dielectric resonators have attractedmuch attention due to their low intrinsic loss and isotropic optical response.In particular, metasurfaces made from silicon dielectric resonators have showndesirable behaviors such as efficient nonlinear optical conversion, spectralfiltering and advanced wave-front engineering. To further explore the potentialof dielectric metamaterials, we present all-dielectric metamaterials fabricatedfrom epitaxially grown III-V semiconductors that can exploit the highsecond-order optical susceptibilities of III-V semiconductors, as well as theease of monolithically integrating active/gain media. Specifically, we createGaAs nano-resonators using a selective wet oxidation process that forms a lowrefractive index AlGaO (n~1.6) under layer similar to silicon dielectricresonators formed using silicon-on-insulator wafers. We further use the samefabrication processes to demonstrate multilayer III-V dielectric resonatorarrays that provide us with new degrees of freedom in device engineering. Forthese arrays, we experimentally measure ~100% reflectivity over a broadspectral range. We envision that all-dielectric III-V semiconductormetamaterials will open up new avenues for passive, active and nonlinear alldielectric metamaterials
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