【摘要】 用低压MOCVD方法生长了InGaAs/InP单量子阱及多量子阱结构。用低温光致发光方法研究了量子阱样品因量子尺寸效应引起的激子能量移动以及激子谱线线宽同量子阱阱宽的关系,7A阱宽的激子能量移动达370meV。选取Q_c=△E_c/△E_g=0.4,采用修正后的Kronig-Penny模型,考虑能带的非抛物线性,拟合了激子能量移动和阱宽的关系曲线。用有效晶体近似方法（VCA）分析了激子尺寸范围内界面不平整度以及合金组分无序对激子谱线线宽的影响。以界面不平整度参量δ₁和δ₂,合金组分元序参量r_c为拟合参数,拟合了激子线宽对阱宽的关系曲线。取δ₁=2.93A,δ₂=100A,r_c=3ML,理论拟合值与实验值符合较好。更多还原

【Abstract】 Single and multiple InGaAs/InP quantum well structures were grown by MOCVD at50mbar. Phototuminescence method was used to characterize the relation between the excitonenergy shift and the well width caused by quantum size effect. The energy shift of a 7A quantumwell was as high as 370meV. Considering the nonparabolic nature of the bands, we tookQ_c=△E_c/△E_g=0. 4, and got a curve about energy shift and width, which was a good fit forthe experimental points. Virtul Crystal Approximation （VCA） method was applied to discussthe dominant mechanism for the linewidth broadening over the extent of exciton. With the interfacemicroscopic fluctuations δ₁=2.93A,δ₂ =100A ,and the radius of the cluster in the alloyR_c=3ML, variation of the exciton photoluminescence linewidth Γ as a function of wellwidth d was obtained, which was also a very good approximation to the experimental results.更多还原