Effect of Growth Temperature on InP QD Lasers

Sch. of Phys. & Astron., Cardiff Univ., Cardiff, UK
IEEE Photonics Technology Letters (Impact Factor: 2.11). 02/2010; 22(2):88 - 90. DOI: 10.1109/LPT.2009.2036245
Source: IEEE Xplore


We describe the effect of growth temperature on the optical absorption, gain, and threshold current density of 730-nm emitting, metal-organic vapor phase epitaxy (MOVPE) grown, InP-AlGaInP quantum-dot lasers. Decreasing the growth temperature from 750??C to 690??C leads to an increase in ground state absorption, while sufficient optical gain and low 300 K threshold current density is obtained in the growth temperature window between 710??C and 730??C . Wider (16 nm compared to 8 nm) interlayer barriers lead to lower threshold current density with 300 K values as low as 165 Acm-2 for 2-mm-long lasers with uncoated facets.

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