用光荧光谱(PL)研究了GaNxAs1-x/G aAs单量子阱(SQW)的光跃迁性质和带阶.通过研究积分荧光强度与激发强度的关系及光谱峰 值位置与温度的关系,发现GaNxAs1-x/GaAs单量子阱中的发光是本征带- 带跃迁,并且低温发光是局域激子发光.通过自洽计算发现它的导带带阶(ΔEc)与氮含 量的关系不是纯粹的线性关系,其平均变化速率(0.110eV/N%)比文献中报道的要慢得多(0.15 6～0.175eV/N%),此外发现Qc(=ΔEc／ΔEg)随氮含量的变化很小,可以用Qc≈x 0.25来表示.还研究了GaNxAs1-x/GaAs单量子阱中氮含量的变化对 能带弯曲参数(b)的影响.%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).
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