Germanium and Silicon Oxide Nanolenses

2 and 1.5 pm, respectively. The significant increase in reflectivity at 1.5 pm for samples with Ge-nanolens stacks indicated that they could be potentially useful for photodetectors operating in the telecommunication range [8]. 

Formation of multilayered Ge/Si02 nanolenses, (a) As-grown layered structure, (b) Initial stage of etching that introduces V-shaped grooves, (c) Final structure with multilayered Ge/ Si02 nanolenses. (Source Chen, H.C., S.W. Lee, and L.J. Chen. 2007. Advanced Materials, 19(2), 222-226. With permission.) 

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