Tunable narrow linewidth AlGaInP semiconductor disk laser for Sr atom cooling applications

We report a frequency stabilised semiconductor disk lasers based on AlGaInP and operating at 689 nm, a wavelength of interest for atomic clocks based on strontium atoms. With a gain structure designed for emission at around 690 nm, more than 100 mW of output power was generated in single frequency operation. We show that the source can be tuned over 8 nm with picometer precision. By servo-locking the frequency to the side of fringe of a reference cavity, we demonstrate rms frequency noise of 5.2 kHz