Abstract
To bypass indirect bandstructure limitations in Ge and have it effectively emitting, we employ light down conversion process at elevated temperatures (emissivity enhancement technique). By applying short wavelength pump light (λin, interband electron transitions), we enhance thermal emission output in the spectral range of intraband electron transitions (λout, free carrier absorption band). We experimentally realized conditions (λin = 1.9 μm, λout = 2–25 μm, T = 380 K) when Ge wafers demonstrated power conversion efficiency of 21% and external quantum efficiency (photon multiplication coefficient) of 130%. Advantages of Ge over Si and ways to realize Ge-based radiative cooler are discussed.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
