Chen, Wei TingKhorasaninejad, MohammadrezaZhu, Alexander Y.Oh, JaewonDevlin, Robert C.Zaidi, AunCapasso, Federico2019-09-172017Chen, Wei Ting, Mohammadreza Khorasaninejad, Alexander Y. Zhu, Jaewon Oh, Robert C. Devlin, Aun Zaidi, and Federico Capasso. 2016. “Generation of Wavelength-Independent Subwavelength Bessel Beams Using Metasurfaces.” Light: Science & Applications 6 (5): e16259–e16259. https://doi.org/10.1038/lsa.2016.259.2047-75382095-5545http://nrs.harvard.edu/urn-3:HUL.InstRepos:41371409Bessel beams are of great interest due to their unique non-diffractive properties. Using a conical prism or an objective paired with an annular aperture are two typical approaches for generating zeroth-order Bessel beams. However, the former approach has a limited numerical aperture (NA), and the latter suffers from low efficiency, as most of the incident light is blocked by the aperture. Furthermore, an additional phase-modulating element is needed to generate higher-order Bessel beams, which in turn adds complexity and bulkiness to the system. We overcome these problems using dielectric metasurfaces to realize meta-axicons with additional functionalities not achievable with conventional means. We demonstrate meta-axicons with high NA up to 0.9 capable of generating Bessel beams with full width at half maximum about as small as similar to lambda/3 (lambda = 405 nm). Importantly, these Bessel beams have transverse intensity profiles independent of wavelength across the visible spectrum. These meta-axicons can enable advanced research and applications related to Bessel beams, such as laser fabrication, imaging and optical manipulation.en-USJournal Article2019-09-1710.1038/lsa.2016.259