Multiwavelength polarization-insensitive lenses based on dielectric metasurfaces with meta-molecules
Metasurfaces are nano-structured devices composed of arrays of subwavelength scatterers (or meta-atoms) that manipulate the wavefront, polarization, or intensity of light. Like other diffractive optical devices, metasurfaces suffer from significant chromatic aberrations that limit their bandwidth. Here, we present a method for designing multiwavelength metasurfaces using unit cells with multiple meta-atoms, or meta-molecules. Transmissive lenses with efficiencies as high as 72% and numerical apertures as high as 0.46 simultaneously operating at 915 nm and 1550 nm are demonstrated. With proper scaling, these devices can be used in applications where operation at distinct known wavelengths is required, like various fluorescence microscopy techniques.
© 2016 Optical Society of America. Received 25 March 2016; revised 18 May 2016; accepted 24 May 2016 (Doc. ID 261932); published 10 June 2016. Funding. National Science Foundation (NSF) (1512266); Samsung; Defense Advanced Research Projects Agency (DARPA); U.S. Department of Energy (DOE) (DE-SC0001293). Acknowledgment. The device nanofabrication was performed at the Kavli Nanoscience Institute at Caltech.
Submitted - 1601.05847v1.pdf
Published - optica-3-6-628.pdf
Supplemental Material - optica-3-6-628_si.pdf