Temperature-dependent power generation from HgCdTe and III–V thermoradiative diodes

Abstract

Thermoradiative power generation, wherein the radiative exchange between a device and its environment leads to the generation of power, is driven by the radiant temperature differential. However, the optoelectronic properties of the device, namely, non-radiative processes such as impact ionization, are also highly temperature dependent. Thus, the optimum temperature for power generation in thermoradiative diodes is governed by the interplay between increasing current from larger temperature differentials and decreased voltage from increasing non-radiative processes. Here, we study the temperature-dependent external quantum efficiency (EQE), dynamic resistance, and thermoradiative power generation from a range of commercially available HgCdTe and III-V diodes ranging from nominal bandgaps of 4–10.6 μm. We conclude that for moderate temperatures and bandgaps, HgCdTe diodes deliver higher power densities than III-V diodes, but only III-V devices can operate at the elevated temperatures that may be required for some applications.