物理学报2017，Vol.66Issue(7)：376-381,6.DOI:10.7498/aps.66.077301
缓冲层对量子阱二能级系统中电子子带间跃迁光吸收的影响
Buffer layer influence on light absorption of electron intersubband transition in binary energy level systems of quantum wells
摘要
Abstract
Due to the restriction of the ZnO buffer layer on the left barrier in a wurtzite asymmetric ZnO/MgxZn1-xO single quantum well (QWs) structure with finite barriers,the other factors such as the size of the well and right barrier,and Mg component,etc.will influence the critical value of the left barrier width to form a binary level energy system.By adopting a finite difference method to solve the SchrSdinger equation,the eigenstates and eigenenergies of electrons in a two-dimensional electron gas are obtained,and the influences of buffer layer ZnO,size and ternary mixed crystal effects on the formation of binary energy level system in QW are discussed.In our computation,the influences of energy band bending,material doping and built-in electric fields on a realistic heterostructure potential are considered.Furthermore,based on the Fermi's golden rule,the optical absorption coefficient of electronic intersubband transition in QW and the influences of buffer layer thickness,the widths of left barrier,well and right barrier and ternary mixed crystal effects are discussed.Our results indicate that the critical width of left barrier increases with the increases of the right barrier width and buffer layer thickness for a binary energy level system of ZnO/MgxZn1-xO single quantum well with a ZnO buffer layer on the left side.However,the critical width of left barrier decreases with the increase of well width and Mg component.Besides,the buffer layer thickness,the widths of left barrier,well and right barrier and ternary mixed crystal also affect the light absorption induced by the electronic intersubband transitions.The increases of Mg component,the widths of right barrier and left barrier will increase the absorption peak and produce its blue-shift.Whereas,increasing well width will reduce the absorption peak and produce its red-shift.The above conclusions are expected to give theoretical guidance in improving the opto-electronic properties of materials and devices made of these heterostructures.关键词
ZnO缓冲层/ZnO/MgxZn1-xO量子阱二能级系统/电子子带间跃迁/三元混晶Key words
ZnO buffer layer/binary energy level system of ZnO/MgxZn1-xO quantum well/electron intersubband transition/ternary mixed crystal引用本文复制引用
李群,屈媛,班士良..缓冲层对量子阱二能级系统中电子子带间跃迁光吸收的影响[J].物理学报,2017,66(7):376-381,6.基金项目
国家自然科学基金(批准号:61274098,11304142)资助的课题.Project supported by the National Natural Science Foundation of China (Grant Nos.61274098,11304142). （批准号:61274098,11304142）
