Direct Modulation Capabilities of Micro-Integrated Laser Sources in the Yellow–Green Spectral Range

In this letter, the millisecond modulation capabilities of high power multisection diode laser systems and their application to second harmonic generation (SHG) are investigated. Different modulation methods of the optical output power of a distributed Bragg-reflector tapered diode laser and a master oscillator power amplifier (MOPA), both emitting at 1120 nm, are compared. The modulated optical output power features a rectangular pulse shape with pulse lengths in the low millisecond regime and peak optical power above 5 W. Based on these results, the most suitable method for the modulation of the second harmonic emission is identified and applied to micro-integrated modules with an MOPA pump source and different crystals for SHG. At an emission wavelength of 560 nm, rectangular millisecond pulses with a peak power of more than 245 mW are achieved.