High Efficient Ultrathin GaAs Optical Absorption Devices with Ring-shaped Nanohole Arrays

We have proposed ultrathin GaAs film with ring-shaped nanohole arrays (RNHs). By tailoring the inner and outer radii of RNHs properly and combining antireflection coating (ITO) and back-reflector (Ag), the photocurrent (26.40 mA/cm
²
) generated in the GaAs based dielectric-semiconductor-metal (DSM) configuration can be increased dramatically by 133.2% with respect to the planar counterpart of equivalent thickness (46 nm). This work provides a promising way to harvest broadband/wide-angle incident light toward high efficient ultrathin GaAs photovoltaic and other optoelectronic devices.