The effect of bias feed profile on spectral properties of noisy Josephson flux flow oscillator

For creation of a noisy non-stationary spectrometer working in the subTHz frequency range the power and spectral characteristics of a flux flow oscillator (FFO), based on a long Josephson junction are studied. The effect of various bias current profiles on the spectral linewidth of long overlap Josephson junction are investigated and comparison with the inline junction geometry is outlined. It has been demonstrated that the spectral linewidth can be increased by a factor of three with the moderate reduction of emitted power.