Dielectric metasurfaces for complete control of phase and polarization with subwavelength spatial resolution and high transmission
Metasurfaces are planar structures that locally modify the polarization, phase and amplitude of light in reflection or transmission, thus enabling lithographically patterned flat optical components with functionalities controlled by design. Transmissive metasurfaces are especially important, as most optical systems used in practice operate in transmission. Several types of transmissive metasurface have been realized, but with either low transmission efficiencies or limited control over polarization and phase. Here, we show a metasurface platform based on high-contrast dielectric elliptical nanoposts that provides complete control of polarization and phase with subwavelength spatial resolution and an experimentally measured efficiency ranging from 72% to 97%, depending on the exact design. Such complete control enables the realization of most free-space transmissive optical elements such as lenses, phase plates, wave plates, polarizers, beamsplitters, as well as polarization-switchable phase holograms and arbitrary vector beam generators using the same metamaterial platform.
© 2015 Macmillan Publishers Limited. Received 14 March 2015 Accepted 20 July 2015 Published online 31 August 2015. This work was supported by the Caltech/JPL President and Director Fund (PDF) and the Defense Advanced Research Projects Agency (DARPA). Y.H. was supported as part of the Department of Energy (DOE) 'Light–Material Interactions in Energy Conversion' Energy Frontier Research Centre under grant no. DE-SC0001293 and a Japan Student Services Organization (JASSO) fellowship. Device nanofabrication was performed at the Kavli Nanoscience Institute at Caltech. The authors thank D. Fattal and C. Santori for discussions. Contributions: A.A. and A.F. conceived the experiment. A.A., Y.H. and M.B. fabricated the samples. A.A. performed the simulations, measurements and analysed the data. A.A. and A.F. co-wrote the manuscript. All authors discussed the results and commented on the manuscript. The authors declare no competing financial interests.
Submitted - 1411.1494
Supplemental Material - nnano.2015.186-s1.pdf