High-peak-power pulse generation with GHz repetition rate using a Q-switched 1060nm DBR tapered laser

Experimental results from a Q-switched three section tapered laser, with an InGaAs triple quantumwell (TQW) active region, consisting of a 2000 μm long tapered element, a 1000 μm ridge waveguide (RW) section and a 1000 μm long passive grating section with a 6th order surface grating were fabricated and investigated. For the generation of short optical pulses the tapered section was biased with a dc-current and the RW absorber section was modulated by a 1 GHz sinusoidal current. By biasing the tapered section with 4 A cw current and GHz sinusoidal modulation of the RW section, short pulses of ~75 ps width and a pulse power of 6.3 W corresponding to 470 pJ pulse energy is reached. The Q-switched pulses are single mode with a central emission wavelength of ~1064 nm and a FWHM spectral width ≤ 0.05 nm.