Transient chirp in high-speed photonic-crystal quantum-dot lasers with controlled spontaneous emission.

We report on a series of experiments on the dynamics of spontaneous emission controlled nanolasers. The laser cavity is a photonic-crystal slab cavity, embedding self-assembled quantum dots as gain material. The implementation of cavity electrodynamics effects increases the large signal modulation bandwidth significantly, with measured modulation speeds of the order of 10 GHz while keeping an extinction ratio of 19 dB. A linear transient wavelength shift is reported, corresponding to a chirp of less than 100 pm for a 35 ps laser pulse. We observe that the chirp characteristics are independent of the repetition rate of the laser up to 10 GHz.