Ardakani Abbas Ghasempour, Mahdavi Seyed Mohammad, Bahrampour Ali Reza
Department of Physics, Sharif University of Technology, Tehran, Iran.
Appl Opt. 2013 Feb 20;52(6):1317-24. doi: 10.1364/AO.52.001317.
Time-dependent model is presented to simulate random lasers in the presence of an inhomogeneous gain medium. PbSe quantum dots (QDs) with an arbitrary size distribution are treated as an inhomogeneous gain medium. By introducing inhomogeneity of the PbSe QDs in polarization, rate, and Maxwell's equations, our model is constructed for a one-dimensional disordered system. By employing the finite difference time-domain method, the governing equations are numerically solved and lasing spectra and spatial distribution of the electric field are calculated. The effect of increasing the pumping rate on the laser characteristics is investigated. The results show that the number of lasing modes and their intensities increase with pumping rate. It is also demonstrated that the emission spectra depend on the standard deviation of the Gaussian distribution function. Increasing the standard deviation leads to reduction of the laser intensity.
提出了一种时间相关模型，用于模拟存在非均匀增益介质时的随机激光器。具有任意尺寸分布的PbSe量子点（QDs）被视为非均匀增益介质。通过在极化、速率和麦克斯韦方程中引入PbSe量子点的不均匀性，构建了用于一维无序系统的模型。采用时域有限差分法，对控制方程进行数值求解，并计算出激光光谱和电场的空间分布。研究了提高泵浦速率对激光特性的影响。结果表明，激光模式的数量及其强度随泵浦速率的增加而增加。还表明发射光谱取决于高斯分布函数的标准差。增加标准差会导致激光强度降低。
