Experimental investigation of the effect of wetting-layer states on the gain–current characteristic of quantum-dot lasers

Matthews, D. R.; Summers, H. D.; Smowton, P. M.; Hopkinson, M.
December 2002
Applied Physics Letters;12/23/2002, Vol. 81 Issue 26, p4904
Academic Journal
Using experimental measurements of the gain-current characteristic as a function of temperature in InGaAs quantum-dot lasers, we demonstrate that it is the population of wetting-layer states that leads to a saturation of the population inversion in dot states and hence to the saturation of gain in a quantum-dot laser. At 300 K, the maximum modal gain for a three-layer structure is reduced from 53 to 14 cm[sup -1].


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