Multi-Junction Laser Power Converters Exceeding 50% Efficiency in the Short Wavelength Infrared

Photonic or laser power converters are crucial components in power-by-light systems. However, their use in long-distance applications has been hindered by low efficiencies and output voltages within the optical fiber transmission window of 1.3-1.6 μm laser wavelengths. Here, we improve and simplify the design and characterization processes for photonic power converters, exceeding 50% efficiency under 1.446 μm laser light. We develop a calibrated model predicting efficiency gains with increasing bandgap, reaching up to 57% efficiency at a 1.3-μm wavelength. As a first demonstration, we produce a high-efficiency device designed by the model: a four-junction InGaAsP photonic power converter with a conversion efficiency of 53.6% ± 1.3% and an output voltage above 2 V under 15.2 W/cm2 of 1.446 μm laser light. These advances open new, practical pathways for integrating photonic power converters into telecommunication systems and unlock the potential to further optimize their design with machine learning algorithms trained with our predictive model.