Duration: 36 months
High-power laser transmission (HPLT) is one of the most promising power transfer technologies due to its ability to send energy without electrical conductors. It uses monochromatic light to transfer energy to a remote system via a laser power converter (LPC). Today, GaAs LPCs possess record efficiencies, with values around 69% at a low power density of 11 W/cm2. However, they are limited by a strong decrease in the efficiency with light intensity due to the unavoidable series resistance losses caused by the low energy gap (Egap) of GaAs. This project aims to develop a novel high-efficiency laser converter for intensities higher than 1kW/cm2, which will create a breakthrough in HPLT. The project tackles current HPLT limitations using two strategies: i) introducing a new material with high energy gap and ii) developing novel LPC architectures. This approach is based on gallium nitride (GaN), a direct band gap material with Egap > 3.4 eV (240% higher than GaAs) and on innovative device architectures with Rs~10-4 Ohm cm2 (>10 times lower than GaAs). This material can handle higher temperatures than GaAs or other low bandgap materials, it has a high breakdown electric field, electron mobility and saturation velocity. This material is currently at the forefront of optoelectronics (LEDs, solar cells, photodetectors, etc.) and high-power electronics, facilitating the development of devices with increased power, reduced on-resistance. This revolutionary technology seeks to: i) obtain a LPC with an efficiency > 80%, and ii) increase the power density transferred more than 2 orders of magnitude. Our project offers a paradigm shift, transferring power up to kilowatts to several kilometers distance. The larger power density allows reducing the LPC surface and the battery size. This proposal offers new disruptive solutions to power remote systems, being of great interest for outer space and deep space applications, such as remote sensors and actuators, robots, and satellites.
