Re-growth free single mode lasers based on slots suitable for photonic integration

The single mode laser structure based on etched slots suitable for photonic integration is presented in this paper. The laser is made completely dependent on a group of slots on one side of the laser cavity. The fabricated 750 μm long single section laser exhibits a threshold current and a slope efficiency of about 32 mA and 0.11 mW/mA, respectively. The stable single mode operation has been observed with a side mode suppression ratio (SMSR) of around 47 dB at a current injection of 100 mA for the fabricated laser. To solve the yield problem associated with the cleaving of the laser structure, the two-section single mode laser based on slots was further present. By tuning the back section current, stable single mode performance with a SMSR of more than 42 dB is observed over a wide temperature from 15°C to 65°C for the fabricated 750 μm long two-section laser. The presented laser structure just needs a single wafer growth and can be fabricated by standard photolithography and has very strong potential for use in optical communication systems.