Broadband enhancement of thermal radiation

Broadband thermal radiation sources are critical for various applications including spectroscopy and electricity generation. However, due to the difficulty in simultaneously achieving high absorptivity and low thermal mass these sources are inefficient. We show a platform that enables one to obtain enhanced emission by coupling a thermal emitter to an optical cavity. We experimentally demonstrate broadband enhancement of thermal emission between lambda similar to 2 - 4.2 mu m using an inherently poor thermal emitter consisting of tens of nanometers thick SiC film with 10% emissivity (epsilon(S)(iC) similar to 0.1). We measure over twofold enhancement of total emission power over the entire spectral band and threefold enhancement of thermal emission over 3 to 3.4 mu m. Our platform has the potential to enable development of ideal blackbody sources operating at substantially lower heating powers. (C) 2019 Optical Society of America under the terms of the OSA Open Access Publishing Agreement