Perspective on photovoltaic optical power converters

Optical wireless power transmission (OWPT) can be used for applications that cannot access traditional power using metal wires. Photovoltaic power-converting III-V semiconductor devices are the core components required for achieving such remote and galvanically isolated power deployments. The development of high-efficiency power converters has already propelled several sensors and probe applications. This growing applied physics field is leveraging the use of ubiquitous laser diode products, now commonly available at various wavelengths. Novel multijunction designs, based on the vertical epitaxial heterostructure architecture devices, have recently allowed fiber-based and free-space applications to quickly progress to higher electrical powers and to benefit from other laser wavelengths. Here, we discuss the perspectives of such multijunction power converters from the viewpoint of realizing additional OWPT deployments and for enabling more probe, sensor, or electronic subsystem power capabilities. The Perspective hence provides a roadmap for devices achieving not only higher conversion efficiency, but also elaborates on the practical aspects necessary to concurrently push the power converters to higher output powers. The photovoltaic multijunction power-converting device is particularly a game-changer for smartly increasing the output voltage and therefore maintaining practical optimal external loads at high laser input powers. Examples of conversion efficiencies above 60% for output powers up to 17.5 W are demonstrated at similar to 808 nm in this study, and up to 22 W of output power is obtained with an efficiency of 48.9% at similar to 980 nm.

Automated summary

Optical wireless power transmission using III-V semiconductor devices for high-efficiency power conversion is a promising technology for applications that cannot access traditional power sources. The development of novel multijunction designs has enabled fiber-based and free-space applications to progress to higher electrical powers, utilizing laser diode products available at various wavelengths. Advancements in photovoltaic multijunction power-converting devices have demonstrated high conversion efficiencies and output powers in this study, showing potential for enabling more probe, sensor, and electronic subsystem power capabilities.