Efficiency of negative-illumination photovoltaic energy conversion

Abstract

Infrared diodes generate electricity from thermal radiation emitted from themselves. The negative process of photovoltaic effect has been expected for application to energy harvesting systems converting from terrestrial radiation. However, its energy conversion efficiency has been known to be very low. In this paper, we investigate energy conversion efficiency and external quantum efficiency for the negative-illumination photovoltaic effect with a systematic measurement for infrared diodes faced to a sufficiently cold surface. We find that the external quantum efficiency reaches 60\ \% for a diode at a temperature, while the energy conversion efficiency stays below 10^-4 %. We indicate dominant parameters for the efficiencies and propose how to improve energy conversion efficiency.