2016/11/10 by Ganapati, Vidya, Xiao, T. Patrick, Yablonovitch, Eli
#FOS: Physical sciences #Optics (physics.optics)
paper · doi:10.48550/arxiv.1611.03544
Thermophotovotaics convert thermal radiation from local heat sources to electricity. A new breakthrough in creating highly efficient thin-film solar cells can potentially enable thermophotovoltaic systems with unprecedented high efficiency. The current 28.8% single-junction solar efficiency record, by Alta Devices, was achieved by recognizing that a good solar cell needs to reflect infrared band-edge radiation at the back surface, to effectively recycle infrared luminescent photons. The effort to reflect band-edge luminescence in solar cells has serendipitously created the technology to reflect all infrared wavelengths, which can revolutionize thermophotovoltaics. We have never before had such high back reflectivity for sub-bandgap radiation, permitting step-function spectral control for the first time. Thus, contemporary efficiency advances in solar photovoltaic cells create the possibility of realizing a >50% efficient thermophotovoltaic system.