Edge-emitting InGaAs/GaAs laser
The TWL wafer has been grown by metal-organic chemical vapour deposition. Laser parameters have been investigated both in pulsed and CW mode in the temperature range of 15–60 ◦C. In the temperature window of 20–50 ◦C under CW excitation the lasers have shown high wavelength temperature stability with the temperature shift of 0.05 nm K−1 and threshold current stability with the characteristic temperature of 500 K. The data obtained prove the concept of thermal stability in tilted wave lasers.
Conclusions
From the research that has been carried out, we can conclude that the concept of an edge-emitting tilted wave laser allows increasing dramatically the temperature stability of the lasing wavelength as the wavelength is fixed by the cavity mode. The TWLs based on InGaAs/GaAs quantum wells have shown extremely high temperature stability of the lasing wavelength 0.05 nm K−1 in the temperature window of 20–50 ◦C. The range may be enlarged if the laser active region has a broader gain spectrum while the thickness of the coupled waveguide is reduced. Specific laser mode formation in the TWL is also responsible for the high temperature stability of threshold current, which has been confirmed by the characteristic temperature as high as 500 K.We believe that the TWLconcept is not limited by the material used and may be transferred to edge-emitting lasers emitting in the other wavelength ranges.
Source and full article: http://www.iop.org/EJ/abstract/0268-1242/25/4/045003/