High-efficiency multi-junction photovoltaic laser power converters for various power and spectral range applications

Stable and reliable optical power converting devices have been obtained for various Optical Wireless Power Transmission (OWPT) applications, including power-over-fiber (PoF) or power beaming uses. They are obtained using vertical multi-junction laser power converters (LPCs) based on the GaAs and InP material systems. The LPCs are high-performance photovoltaic (PV) devices typically optimized for a narrow wavelength range. Such Optical Power Converters (OPCs) enable several isolated electrical power or remoter power applications using high-power lasers for their input power. Broadcom's vertical multijunction PV devices (VEHSA design) permit optical-to-electrical conversion with record efficiencies and output power capabilities. This presentation will review the recent developments in both, the GaAs-based and InP-based systems. For example, high-efficiency and high-power capabilities have recently been demonstrated at ~1480nm for the InP-based PT10-InGaAs/InP, which are designed with 10 InGaAs subcells lattice-matched to InP and connected with transparent tunnel junctions. These long-wavelength OPCs are capable of directly producing electrical output voltages in the 5 V range.