Jiang Li, Asryan Levon V
Department of Materials Science and Engineering, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA.
Nanotechnology. 2008 Oct 15;19(41):415204. doi: 10.1088/0957-4484/19/41/415204. Epub 2008 Sep 3.
Effect of spatial hole burning (SHB) and multi-longitudinal-mode generation on high power operation of a quantum dot (QD) laser is studied. We use a set of rate equations for confined carriers in QDs, free carriers in the optical confinement layer and photons. The threshold currents and output powers of modes are computed numerically. The power of the main mode is reduced due to lasing of higher-order modes and spatially nonuniform carrier distribution. As a new mode turns on, kinks appear in the light-current curves (LCCs) of existing modes. SHB reduces the total optical power of a laser and contributes to nonlinearity of the overall LCC. The effect is more significant when any of the parameters of the structure is close to its critical tolerable value. The LCC becomes more linear with improving QD-size uniformity or increasing surface density of QDs or cavity length.
研究了空间烧孔（SHB）和多纵模产生对量子点（QD）激光器高功率运行的影响。我们使用了一组针对量子点中受限载流子、光学限制层中的自由载流子和光子的速率方程。通过数值计算得出了各模式的阈值电流和输出功率。由于高阶模式的激射和空间上不均匀的载流子分布，主模式的功率降低。当新的模式开启时，现有模式的光电流曲线（LCC）中会出现扭结。SHB降低了激光器的总光功率，并导致整体LCC的非线性。当结构的任何参数接近其临界容忍值时，这种效应更为显著。随着量子点尺寸均匀性的提高、量子点表面密度的增加或腔长的增加，LCC变得更加线性。
