We experimentally examined the propagation of temporally square modulated optical pulses through a coupled ring resonator. Sharp transient spikes appeared as the square pulses entered the system. The main signal gradually grew up through coupled-resonator-induced transparency (CRIT), with the time constant determined by a second resonator. Transient spikes were attributed to the higher and lower spectral components of the incident pulse, to which the resonators cannot respond; hence, they were interpreted as optical precursors. The experiments, therefore, demonstrated that precursors and the main signal can be observed separately, with amplitudes comparable to that of the incident step in CRIT.
© 2012 Optical Society of America
Original Manuscript: April 19, 2012
Revised Manuscript: May 21, 2012
Manuscript Accepted: May 22, 2012
Published: July 13, 2012
Tohru Oishi, Ryuta Suzuki, Parvin Sultana, and Makoto Tomita, "Optical precursors in coupled-resonator-induced transparency," Opt. Lett. 37, 2964-2966 (2012)