采用磁控溅射法在蓝宝石衬底上制备了结晶良好的Mg₂Si多晶薄膜，研究了退火温度（375~475 ^oC）对薄膜晶体结构、表面形貌、拉曼光谱和光学性质的影响。X射线衍射（XRD）结果表明，当退火温度为400 ^oC时Mg₂Si (220) 衍射峰强度最强，样品结晶质量最好，未见明显可观测的MgO相。扫描电镜（SEM）结果表明，所有样品表面均呈现清晰可见的规则六边形，且退火温度对形貌影响较小。拉曼光谱结果显示所有样品均呈现出Mg₂Si薄膜的特征峰（256 cm^-1附近的F_2g振动模），同时出现345 cm^-1附近的F_1u (LO)声子模，表明生成样品均为结晶良好的Mg₂Si薄膜。对薄膜光学性质的研究结果表明，随着退火温度升高，样品光学带隙先增大后减小。

在250 ℃的低温下，以三甲基镓、四（二甲氨基）钛为前躯体源，O₃为反应气体，采用热原子层沉积制备了Ti掺杂Ga₂O₃（TGO）薄膜。Ga₂O₃和TiO₂的生长速率分别为0.037 nm/cycle和0.08 nm/cycle，TGO薄膜厚度低于理论计算值。X射线光电子能谱仪测试结果表明膜中Ti浓度随Ga₂O₃/TiO₂循环比减少而增加，O 1s、Ga 2p和Ti 2p的峰位置向较低的结合能移动，这是因为Ti原子取代了Ga原子的某些位点引起了结合能降低，表明Ti元素成功掺杂到Ga₂O₃薄膜中。TiO₂和Ga₂O₃的芯能级光谱分析表明薄膜中存有Ti⁴⁺和Ga³⁺离子。TGO薄膜的O 1s芯能级光谱中Ga-O键随着Ti-O键含量增加而下降，表明TGO薄膜中形成Ga₂O₃-TiO₂复合材料。掠入射X射线衍射图中没有出现衍射峰，表明沉积的Ga₂O₃和TGO薄膜为非晶态。原子力显微镜观察到薄膜表面平整光滑，均方根粗糙度为0.377 nm，这得益于原子层沉积逐层生长的优势。TGO薄膜在可见光区表现出较高的透明度，对紫外光强烈吸收。随着Ti掺杂浓度的增加，TGO薄膜的折射率由于化学变化从1.75增加到1.99，紫外光区消光系数增大引起透过率减小，吸收边缘出现了红移，光学带隙从4.9 eV减小到4.3 eV。分光光度法和X射线光电子能谱法测定薄膜光学带隙所得的结果一致。

Colloidal CdSe quantum dots (QDs) are promising materials for solar cells because of their simple preparation process and compatibility with flexible substrates. The QD radiative recombination lifetime has attracted enormous attention as it affects the probability of photogenerated charges leaving the QDs and being collected at the battery electrodes. However, the scaling law for the exciton radiative lifetime in CdSe QDs is still a puzzle. This article presents a novel explanation that reconciles this controversy. Our calculations agree with the experimental measurements of all three divergent trends in a broadened energy window. Further, we proved that the exciton radiative lifetime is a consequence of the thermal average of decays for all thermally accessible exciton states. Each of the contradictory size-dependent patterns reflects this trend in a specific size range. As the optical band gap increases, the radiative lifetime decreases in larger QDs, increases in smaller QDs, and is weakly dependent on size in the intermediate energy region. This study addresses the inconsistencies in the scaling law of the exciton lifetime and gives a unified interpretation over a widened framework. Moreover, it provides valuable guidance for carrier separation in the thin film solar cell of CdSe QDs.Colloidal CdSe quantum dots (QDs) are promising materials for solar cells because of their simple preparation process and compatibility with flexible substrates. The QD radiative recombination lifetime has attracted enormous attention as it affects the probability of photogenerated charges leaving the QDs and being collected at the battery electrodes. However, the scaling law for the exciton radiative lifetime in CdSe QDs is still a puzzle. This article presents a novel explanation that reconciles this controversy. Our calculations agree with the experimental measurements of all three divergent trends in a broadened energy window. Further, we proved that the exciton radiative lifetime is a consequence of the thermal average of decays for all thermally accessible exciton states. Each of the contradictory size-dependent patterns reflects this trend in a specific size range. As the optical band gap increases, the radiative lifetime decreases in larger QDs, increases in smaller QDs, and is weakly dependent on size in the intermediate energy region. This study addresses the inconsistencies in the scaling law of the exciton lifetime and gives a unified interpretation over a widened framework. Moreover, it provides valuable guidance for carrier separation in the thin film solar cell of CdSe QDs.

对Sb₂Te₃薄膜的结构、线性光学及非线性吸收性质的Ti掺杂影响进行了系统性探究。利用磁控溅射和高温退火手段制备了不同Ti掺杂浓度的晶态Sb₂Te₃薄膜。X射线光电子能谱分析显示Sb₂Te₃薄膜中的Ti元素以Ti⁴⁺化学态以TiTe₂的形式存在。线性光学性质结果表明，在保持非线性器件中宽工作波长特性的同时，Ti掺杂可以提高Sb₂Te₃薄膜的透射率，并降低光学带隙从1.32 eV至1.25 eV，根据Burstein-Moss理论，这取决于载流子的减少。利用自主搭建的开孔Z扫描系统，测试了薄膜样品在132 GW/cm²强度下800 nm飞秒激光激发的非线性吸收性质，结果显示的Ti掺杂引起的饱和吸收可调谐行为可归因于光学带隙减小与晶化抑制的竞争效应。此外，Ti掺杂将Sb₂Te₃薄膜的激光损伤阈值从188.6 GW/cm²提高到了265.5 GW/cm²。总而言之，Ti掺杂Sb₂Te₃薄膜在非线性光学器件领域具有广泛的应用前景。