Propagation of short lightpulses in microring resonators: ballistic   transport versus interference in the frequency domain
  The propagation of short lightpulses in waveguiding structures with optical feedback, in our case optical microresonators, has been studied theoretically and experimentally. It appears that, dependent on the measurement set-up, ballistic transport or interference in the time domain of fs and ps laser pulses can be observed. The experiments are analyzed in terms of characteristic time scales of the source, the waveguide device and the detector arrangement and are related to Heisenberg's uncertainty principle. Based on this analysis a criterion is given for the upper bitrate for error free data transmission through optical microresonators. 
Alfred Driessen, Douwe H. Geuzebroek, Edwin Klein, Ronald Dekker,   Remco Stoffer, C. Bornholdt
physics.optics quant-ph