Two-Junction III-V Photonic Power Converter Operating At Monochromatic Telecom Wavelengths

We present a two-junction photonic power converter operating under monochromatic illumination in the telecommunications O-band. The design, which is a direct extension of multi-junction solar cell technology, incorporates InAlGaAs absorbing layers lattice-matched to InP. Multi-junction detailed balance calculations are presented to benchmark device performance. A transparent tunnel diode with peak tunneling current near 1000 A/cm2 provides a series connection between the subcells. Current-voltage measurements under laser illumination at 1319 nm yield ideality factors near 1, with open-circuit voltages up to 0.38 V and 0.66 V for the one- and two-junction devices, respectively, under intensities of up to 0.33 W/cm2. Quantum efficiency measurements reveal that the two-junction device is current-matched near 1390 nm.