Mode-locked ultrashort pulse generation from on-chip normal dispersion   microresonators
  We describe the generation of stable mode-locked pulse trains from on-chip normal dispersion microresonators. The excitation of hyper-parametric oscillation is facilitated by the local dispersion disruptions induced by mode interactions. The system is then driven from hyper-parametric oscillation to the mode-locked state with over 200 nm spectral width by controlled pump power and detuning. With the continuous-wave driven nonlinearity, the pulses sit on a pedestal, akin to a cavity soliton. We identify the importance of pump detuning and wavelength-dependent quality factors in stabilizing and shaping the pulse structure, to achieve a single pulse inside the cavity. We examine the mode locking dynamics by numerically solving the master equation and provide analytic solutions under appropriate approximations. 
S.-W. Huang, H. Zhou, J. Yang, J. F. McMillan, A. Matsko, M. Yu, D.-L.   Kwong, L. Maleki, and C. W. Wong
physics.optics nlin.PS