Nanophotonics and dielectric metasurfaces
Optical metamaterials present electromagnetic responses dependent on their structure, rather than chemical properties. In general they are comprised of features smaller than the relevant wavelength of radiation, operating in the nanophotonic regime. Quasi-two-dimensional thin films of metamaterials are known as metasurfaces and are often comprised of discrete, optically resonant features.
Recently, demonstration of the control of light by the introduction of abrupt phase discontinuities across a subwavelength scale has opened the doors to a new level of wavefront control. Work in the field has demonstrated the capability of phased arrays of nanoantennas to manipulate incident light in a highly controllable way. The Escarra Group is developing a class of dielectric nanoantennas capable of arbitrary control over a transmitted wavefront with near unity transmission. This technology has application anywhere precise, tailorable, high efficiency optics are required, including photovoltaics and optical data transmission.
Future pursuits will include dynamically tunable metasurfaces, discretized splitting of the solar spectrum, and coupled 2D semiconductor material-metasurface systems.
“Arbitrary control over a transmitted wavefront can be achieved through the introduction of phase discontinuities across a sub-wavelength scale.”