2 MHz repetition rate, 200 ps pulse duration from a monolithic passively Q-switched microchip laser

We report on a diode-pumped, monolithic and passively Q-switched microchip laser generating 200 ps pulses at a wavelength of 1064 nm with a repetition rate of up to 2 MHz. By varying the pump intensity we can change the repetition rate in the range from 100 kHz to 2 MHz and achieve pulse energies from 400 nJ to 130 nJ respectively, while still maintaining singe transversal and longitudinal mode operation. The microchip laser is based on Nd:YVO4 as the gain medium and a SESAM as the passive Q-switch. It is monolithically bonded with spin-on-glass as the bonding agent. The timing jitter was measured to be shorter than 40 ns for low and 2.5 ns for high repetition rates resulting in a relative timing jitter smaller than 1%. The output of this type of laser can be amplified easily to the range of few tens of watts using only one amplification stage based on a photonic crystal fiber. The combination of picoseconds pulses, high average power and high repetition rates makes this system very interesting for many applications like e.g. micromachining with high processing speed and nonlinear frequency conversion with high average power.