Minimizing the linewidth of the Flux-Flow Oscillator

For the first time the linewidth of Flux-Flow Oscillator has been calculated by direct computer simulation of the sine-Gordon equation with noise. Nearly perfect agreement of the numerical results with the formula derived in [Phys. Rev. B, {\bf 65}, 054504 (2002)] has been achieved. It has been demonstrated that for homogeneous bias current distribution the linewidth actually does not depend on the junction length for practically interesting parameters range. Depending on the length of the unbiased tail, the power may be maximized and the linewidth may be minimized in a broad range of bias currents. The linewidth can be decreased further by 1.5 times by proper load matching.