Photonic crystal laser based on Fano interference allows for ultrafast frequency modulation in the THz range

Replacing a conventional mirror in a photonic crystal laser by one based on Fano interference leads to rich laser dynamics, including realization of stable self-pulsing and potential for ultra-fast modulation. In particular, the narrowband Fano mirror guarantees single-mode operation and significantly alters the modulation response compared to Fabry-Perot lasers. In this work the small-signal response is analyzed using a dynamical model based on coupled-mode theory and rate equations, which shows how the 3-dB bandwidth of the frequency modulation response may exceed tens of THz, orders of magnitude larger than for conventional semiconductor lasers.