Gallium Phosphide Optical Metasurfaces for Visible Light Applications

There are few materials that are broadly used for fabricating optical metasurfaces for visible light applications. Gallium phosphide (GaP) is a material that, due to its optical properties, has the potential to become a primary choice but due to the difficulties in fabrication, GaP thin films deposited on transparent substrates have never been exploited. In this article we report the design, fabrication, and characterization of three different amorphous GaP metasurfaces obtained through sputtering. Although the material properties can be further optimized, our results show the potential of this material for visible applications making it a viable alternative in the material selection for optical metasurfaces.

Mauro Melli, Melanie West, Steven Hickman, Scott Dhuey, Dianmin Lin, Mohammadreza Khorasaninejad, Chieh Chang, Sunny Jolly, Huy Tae, Evgeni Poliakov, Pierre St. Hilaire, Stefano Cabrini, Christophe Peroz, Michael Klug