The optical properties and the band lineup in GaNAs/GaAs single quantum wells (SQWs) grown by molecular beam epitaxy (MBE) usi ng photoluminescence (PL) technique were investigated. It was found that the low -temperature PL is dominated by the intrinsic localized exciton emission. By f i tting the experimental datawith a simple calculation, band offset of the GaN 0.015As0.985/GaAs heterostructure was estimated. Moreover, ΔEc, t he discontinuity of the conduction band was found to be a nonlinear function of the nitrogen composition (x) and the average variation of ΔEc is abou t 0.110eV per % N, such smaller than that reported on the literature (0.156～0.1 75 eV/N%).In addition, Qc has little change whtn N composition increares, wi th an experimential relation of Qc≈x0.25. The band bowing coefficient (b) was also studied in this paper. The measured band bowing coefficient sh ows a strong function of x,giving an experimental support to the theoretic c alculation of Wei Su-Huai and Zunger Alex (1996).%从理论上探讨了红外子带间量子级联激光器向短波段发展的可能性及其根本性困难,用模型固体理论的基本假设、应变能带理论、非抛物性能带的经验二带模型、传播矩阵和分层逼近法,分析计算了以GaSb为衬底的InAs/AlSb,InAs/Al0.6Ga0.4Sb,和以InP为衬底的In0.53Ga0.47As/In0.52Al0.48As的带阶,及其所组成的量子阱在加和不加电场作用下的束缚态.发现其导带最大子带边能量差不可能超过其阱深的56%～62%,而且受到导带间接能谷的限制而进一步减小.设计提出了迄今发射最短波长为2.88μm的由25个周期共250个耦合量子阱组成、外加电场为100kV/cm的子带间量子级联激光器的结构方案.
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