ZnO/MgZnO单量子阱的能带重正化与阱宽的关系  

Well Width Dependence of Band Gap Renormalization of Single ZnO/MgZnO Quantum Well

作　　者：李小龙[1] 姜小芳[1] 雷小燕[1] 丘志仁[1] 张保平[2] 丁才蓉[1] 曾学然[1] 

机构地区：[1]中山大学光电材料与技术国家重点实验室,广东广州510275 [2]厦门大学物理系半导体光子学研究中心,福建厦门361005

出　　处：《光学学报》2010年第10期2967-2971,共5页Acta Optica Sinica

基　　金：国家973计划(2004CB719804);国家自然科学基金(60876007);广州市科技局推荐项目(2005Z3-C7451)资助课题

摘　　要：通过室温下的时间积分光致发光(PL)谱,研究了阱宽Lw渐变的ZnO/Mg0.1Zn0.9O单量子阱在高激发强度下的能带重正化与阱宽的关系。实验中光生载流子浓度为n=1.6×1014cm-2,在Lw从2.3 nm渐变到4.3 nm,PL谱峰位的红移量从5.9 meV变化到97.1 meV。红移量随阱宽增大而增加,但增加率却逐渐减少。当Lw>2αB(αB,ZnO体材料激子玻尔半径,约为2 nm)时,红移量逐渐呈现出饱和的趋势(100 meV)。研究发现峰位的红移是由于多体效应所导致的能隙收缩以及在高的激发强度下带内填充效应的这两种机理相互竞争的结果。Band gap renormalization of ZnO/Mg0.1Zn0.9O single quantum well（QW） with gradual well width（Lw） is studied by room-temperature time integrated photoluminescence（PL） spectra at high excitation power density.The photo-generated carrier density is n=1.6×1014 cm-2 and the magnitude of red shift of PL spectrum peak increases from 5.9 meV to 97.1 meV with Lw changing from 2.3 nm to 4.3 nm.With Lw increaseing,the red shift increases but the increase rate gradually decreases.When Lw2αB（αB,the exciton Bohr radius of ZnO bulk,is about 2 nm）,the red shift starts to be gradually saturated.It is found that the red shift is the competition result of energy gap contraction due to many body effect and intraband filling effect at high excitation power density.The result is useful for designing and application of ZnO QW-based optoelectronic devices.

关 键 词：半导体光学 能隙重正化 光致发光 单量子阱 

分 类 号：O472.3[理学—半导体物理]