Current spreading effects in 680-nm-band self-sustained pulsating AlGalnP visible laser diodes

We have developed 680-nm-band AlGalnP visible laser diodes having very lowintensity noise with stable self-sustained pulsation. The pulsation characteristics were affected by current spreading outside the ridge stripe. We obtained AlGalnP visible laser diodes with stable self-sustained pulsation by optimizing the ridge structure. The lasers achieved relative intensity noise (RIN) as low as-136 dB Hz^–1 in the temperature range 20–50°C at 3 mW.