GaMnN材料红外光谱中洛伦兹振子模型的遗传算法研究

利用红外反射光谱研究了蓝宝石衬底上用金属有机物化学气相淀积方法生长的稀磁半导体GaMnN材料的晶格振动特性. 并成功地将改进的遗传算法应用于其红外反射光谱洛伦兹振子模型参数的提取. 通过与GaN薄膜的洛伦兹振子模型参数的对比研究发现，GaN掺入Mn后，ω_TO向高频方向移动，γ，ε_∞和ε_s均增加，而ω_LO基本保持不变. 文中同时分析和讨论了Mn对晶格振动特性的影响及 关键词： 稀磁半导体GaMnN材料 遗传算法 洛伦兹振子模型 参数提取

A genetic algorithm research on Lorentz oscillator model in infrared spectra of GaMnN

The lattice vibrations of diluted magnetic semiconductor GaMnN epitaxial films grown on sapphire substrates by metalorganic chemical vapor deposition have been investigated using infrared reflectance spectroscopy. The revised genetic algorithm was successfully used to extract the Lorentz oscillator model parameters of GaMnN from infrared reflectance spectra. Comparing the Lorentz oscillator model parameters of GaMnN with those of GaN, it was found that ω_TO moved to higher frequencies, γ, ε_∞ and ε_s increased, but the ω_LO was almost not changed. The effects of Mn on the properties of lattice vibration and the mechanisms of variations of the dielectric function were also analyzed and discussed in this paper.