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用分子束外延法在GaAs衬底上生长了CdSe Cd0 .65Zn0 .3 5Se超晶格结构。利用X射线衍射 (XRD)、77K下变密度激发的光致发光光谱和变温度光致发光光谱研究了CdSe CdZnSe超晶格结构和激光复合特性 ,在该材料中观测到激子激子散射发射峰 ,变密度激发光致发光光谱和变温度光致发光光谱证实了这一现象。激子发射峰的线宽随着温度的升高而展宽 ,低温时发光峰的宽度主要是由合金组分和阱垒起伏引起的 ,高温时激子线宽展宽是由于激子与纵光学声子和离化的施主杂质间的散射作用引起的 ,光致发光的强度随着温度的升高而降低 ,这主要是由激子的热离化造成的 ,也就是说 ,热激发使得电子或空穴由阱中跃迁至垒上
CdSe Cd0.65Zn0.35Se superlattice structure was grown on GaAs substrate by molecular beam epitaxy. The CdSe CdZnSe superlattice structure and laser recombination properties were investigated by X-ray diffraction (XRD), photoluminescence (PLD) and variable temperature photoluminescence (PLG) at 77K. The exciton exciton scattering Peak, variable density excited photoluminescence spectra and variable temperature photoluminescence spectra confirm this phenomenon. The width of the exciton emission peak broadens with increasing temperature. The width of the emission peak at low temperature is mainly caused by the composition of the alloy and the rising of the well barrier. The broadening of the exciton line width at high temperature is due to the exciton and longitudinal optical sound Due to the scattering effect between the daughter and ionized donor impurities, the photoluminescence intensity decreases with increasing temperature, which is mainly caused by the thermal ionization of the excitons, that is, the thermal excitation causes electrons or Holes jump from the well to the base