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用光的反射光谱和光的光致发光光谱的测量对Ga0.69In0.31NxAs1-x/GaAs的单量子阱的光学特性作了研究,在单量子阱的反射光谱中,观察到GaAs能隙之上的Franz-Keldysh振荡和来源于量子阱区的各种类激子跃迁, Franz-Keldysh振荡确定量子阱的内建电场并发现它是随N的浓度增加而增加;反射信号随样品中氮耦合增强而减弱,因为温度降低时载流子的定域作用导致调制效应的弱化。激子跃迁的能量和温度关系按照Varshni和爱因斯坦-玻司方程作了研究,在PL谱中观察到的11 H跃迁能量和谱线展宽的温度反常关系解释为起源于氮耦合所引起的定域态,这种样品的谱线特征为随氮成份增加出现红移,氮结合作用的另一个结果是晶体的性质严重退化,明显地表现线宽受温度的影响增大。总之,氮引进系统会观察到GaAs边带以上的FkO导致内建场增大,有低温时高激发态叠加并屏闭在定域态上的部分调制外场作用的倾向。PL峰能量和线宽对温度的反常关系可以理解为由氮的结合作用引起的形成定域态和去除定域态的竞争结果。
The optical properties of Ga0.69In0.31NxAs1-x / GaAs single quantum wells have been studied by the measurement of the light reflection spectrum and the photoluminescence spectrum. In the single-quantum well reflectance spectrum, Franz-Keldysh oscillations and various kinds of exciton transitions derived from the quantum well region. The Franz-Keldysh oscillation determines the internal electric field of the quantum well and found that it increases with increasing concentration of N; the reflection signal increases with increasing nitrogen coupling in the sample And weakened, because the localization effect of the carrier when the temperature decreases lead to the weakening of the modulation effect. The energy and temperature dependence of exciton transitions was studied according to the Varshni and Einstein-Bolivian equations. The observed temperature anomalies in the 11 H transition energies and spectral broadening in the PL spectrum were interpreted as those originating from the nitrogen coupling Localized state, the spectral characteristics of this sample with the nitrogen composition increases redshift, another result of nitrogen binding is the serious deterioration of the nature of the crystal, the apparent increase in line width by the temperature. In summary, the introduction of nitrogen into the system shows that the FkO above the GaAs sidebands leads to an increase of the built-in field, with the tendency of partial modulation of the external field to superpose and trapped in localized states at low temperatures. The anomalous relationship of PL peak energy and linewidth to temperature can be understood as the competitive result of the formation of localized states and the removal of localized states due to the nitrogen binding.