Temperature and current dependencies of terahertz emission from stacks of intrinsic Josephson junctions with thin electrodes revealed by a high-resolution FT-IR spectrometer

► Terahertz emission was found in Bi2212 mesas with electrodes thickness <100 nm. ► We built an FT-IR spectrometer with the frequency resolution of ∼1 GHz. ► The spectrometer reveals that the emission frequency fp is ∼0.5 THz. ► The linewidth of the emission was found to be less than 1 GHz. ► fp decreases up to 20% with increased temperature and bias current.