非对称Mg_(x)Zn_(1-x)O/ZnO/Mg_(y)Zn_(1-y)O量子阱中杂质态子态跃迁光吸收  

Optical Absorption of Impurity State Inter-Substate Transitions in Asymmetric Mg_(x)Zn_(1-x)O/ZnO/Mg_(y)Zn_(1-y)O Quantum Wells with Mixed Phases

作　　者：王嫣然 昝宇海 屈媛[1] 班士良[1] WANG Yanran;ZAN Yuhai;QU Yuan;BAN Shiliang(School of Physical Science and Technology,Inner Mongolia University,Hohhot O10021,China)

机构地区：[1]内蒙古大学物理科学与技术学院,呼和浩特010021

出　　处：《内蒙古大学学报（自然科学版）》2022年第5期489-499,共11页Journal of Inner Mongolia University：Natural Science Edition

基　　金：国家自然科学基金(61764012)资助项目。

摘　　要：采用密度矩阵法探讨具有混相非对称Mg_(x)Zn_(1-x)O/ZnO/Mg_(y)Zn_(1-y)O量子阱中杂质态子态间跃迁光吸收及其相关的尺寸和混晶效应。在较宽Mg组分x范围内,特别针对纤锌矿和闪锌矿的混相区间(0.37<x<0.62),考虑内建电场和Hartree势的作用,讨论跃迁光吸收系数。结合变分法和有限差分法,获得杂质子态的波函数及其本征能。所得结果表明:与单相只有单个光吸收峰不同,在混相结构中存在两类光吸收峰分别对应纤锌矿和闪锌矿结构。与电子子带间跃迁光吸收相比,获得的杂质子态间跃迁光吸收系数α_(nm)(从n态到m态的跃迁)的峰位出现蓝移,且振幅增大。α_(12)和α_(13)的峰位随着y的增加向较低入射光子波长λ移动(蓝移),但随着阱宽的增加而向较长λ移动(红移),从而调制光探测区域。结果有助于光电探测器的设计和制作。The optical absorption of impurity state inter-substate transitions in asymmetric Mg_(x)Zn_(1-x)O/ZnO/Mg_(y)Zn_(1-y)O quantum wells with mixed phases and related size and ternary mixed crystal effects are investigated using the density matrix method.In a wide range of Mg component x,especially in the mixedphase region(0.37<x<0.62)of Mg_(x)Zn_(1-x)O consisted of wurtzite and zinc-blende phases,the optical absorption coefficients(OACs)are discussed in con-sideration of built in electric fields and the Hartree potential.The impurity sub-state wave functions and corresponding eigen-energies are obtained by combi-ning the variational method with numerical computations.It is found that differ-ent from single phase with only one peak,there are two kinds of peaks in mixed phases corresponding to wurtzite and zinc-blende structures,respectively.Com-pared with the electron inter-subband transitions,our results about OAC anm(the transition from substates n to m)exhibit that impurity state inter-substate transitions are blue shifted and their amplitudes increase.The peaks of a_(12)and a_(13)shift toward lower incident photon wavelengthλ(blue shift)by increasing y and shift toward longerλ(red shift)by enlarging the well width to modulate the photo-detecting region.Our results are helpful for the design and fabrication of optical photo detectors.

关 键 词：光吸收 杂质态子态间跃迁 三元混晶 混相 非对称Mg_(x)Zn_(1-x)O/ZnO/Mg_(y)Zn_(1-y)O量子阱 

分 类 号：O471.3[理学—半导体物理]