Modal absorptions in laser-like heterostructures containing InAs self-assembled quantum dots (QDs) and InGaAs quantum well-dots (QWDs) have been studied. The evaluation of photoresponse as a function of waveguide length has allowed us to determine per-layer modal absorptions of 69 and 13 cm ^-1 for the ground state optical transitions of QWDs and QDs, respectively. The values of the modal absorption can be used as a measure of the maximal (saturated) modal gain. To compare quantum heterostructures with different dimensionality we have introduced the layer gain constant, a parameter characterizing the light transmittance through the absorbing or gaining layer. We have shown that the QWD layer gain constant significantly exceeds quantum well and quantum dot ones.

中文翻译：

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具有 InGaAs 量子阱点异质结构的波导中的饱和层增益

已经研究了包含 InAs 自组装量子点 (QD) 和 InGaAs 量子阱点 (QWD) 的类激光异质结构中的模态吸收。作为波导长度函数的光响应评估使我们能够分别为 QWD 和 QD 的基态光学跃迁确定 69 和 13 cm ^-1的每层模式吸收 。模态吸收的值可以用作最大（饱和）模态增益的量度。为了比较具有不同维度的量子异质结构，我们引入了层增益常数，这是一个表征通过吸收层或增益层的透光率的参数。我们已经证明 QWD 层增益常数显着超过量子阱和量子点。