Effect of Growth Temperature on InP QD Lasers

ArticleinIEEE Photonics Technology Letters 22(2):88 - 90 · February 2010with5 Reads
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<sup>-2</sup> for 2-mm-long lasers with uncoated facets.
  • [Show abstract] [Hide abstract] ABSTRACT: We measured the gain dynamics at the ground-state transition in an electrically pumped InP/AlGaInP quantum-dot optical amplifier at room temperature by femtosecond differential transmission. The gain shows an ultrafast recovery within 200 fs, even faster than in state-of-the-art InAs/GaAs quantum-dot amplifiers. This finding, likely to be due to the less confined and more closely spaced hole levels in InP dots, is promising for optical signal processing at high bit rates.We furthermore measured the pump-induced refractive index changes and deduced a linewidth enhancement factor similar to the one in InAs/GaAs quantum dots.
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    Article · Feb 2011
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    Article · Aug 2011
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