Polarization-insensitive metalenses at visible wavelengths Khorasaninejad, M. Zhu, A. Y. Roques-Carmes, Charles Chen, W. T. Oh, J. Mishra, I. Devlin, R. C. Capasso, F. Metasurface polarization-insensitive metalenses visible wavelength titanium dioxide ddc:530 In this Letter, we demonstrate highly efficient, polarization-insensitive planar lenses (metalenses) at red, green, and blue wavelengths (λ = 660, 532, and 405 nm). Metalenses with numerical apertures (NA) of 0.85 and 0.6 and corresponding efficiencies as high as 60% and 90% are achieved. These metalenses are less than 600 nm-thick and can focus incident light down to diffraction-limited spots as small as ∼0.64λ and provide high-resolution imaging. In addition, the focal spots are very symmetric with high Strehl ratios. The single step lithography and compatibility with large-scale fabrication processes make metalenses highly promising for widespread applications in imaging and spectroscopy. American Chemical Society 2016 info:eu-repo/semantics/article doc-type:article text http://purl.org/coar/resource_type/c_2df8fbb1 https://research-explorer.ista.ac.at/record/21522 Khorasaninejad M, Zhu AY, Roques-Carmes C, et al. Polarization-insensitive metalenses at visible wavelengths. <i>Nano Letters</i>. 2016;16(11):7229-7234. doi:<a href="https://doi.org/10.1021/acs.nanolett.6b03626">10.1021/acs.nanolett.6b03626</a> eng info:eu-repo/semantics/altIdentifier/doi/10.1021/acs.nanolett.6b03626 info:eu-repo/semantics/altIdentifier/issn/1530-6984 info:eu-repo/semantics/altIdentifier/e-issn/1530-6992 info:eu-repo/semantics/altIdentifier/pmid/27791380 info:eu-repo/semantics/closedAccess