物理学报Issue(17)：1-8,8.DOI:10.7498/aps.63.177101
纤锌矿In0.19Ga0.81N/GaN量子阱中光学声子和内建电场对束缚极化子结合能的影响
Effects of optical phonon and built-in electric field on the binding energy of b ound p olarons in a wurtzite In0.19Ga0.81N/GaN quantum well
摘要
Abstract
The energies and binding energies of the bound polarons in a wurtzite In0.19Ga0.81N/GaN quantum well are inves-tigated by means of a modified Lee-Low-Pines variational method. Contributions of ground state binding energies and different branches of a longwave optical phonon mode to the energies and binding energies of the bound polarons as a function of the well width and impurity center position are given. Effects of the anisotropy of phonon frequency and built-in electric field in the system on the energies and binding energies, and the electron and impurity center-optical phonon interaction, are included in the calculations. Results show that the contributions of optical phonons and built-in electric field to the ground state energy and binding energy of the bound polarons in a wurtzite In0.19Ga0.81N/GaN quantum well are very large, and result in the reduction of energy and binding energy. The binding energy decreases monotonically with increasing well width, and the speed of decrease is fast in the narrower well while the speed of decrease is slow in the wider well. Contributions of different branches of phonons to the energies and binding energies as a function of well width are different. In the narrower well, contributions of the confined phonon (withoud built-in electric field) are smaller than those of the interface and half-space phonons, while in the wider well, contributions of the confined phonons are larger than those of the interface and half-space phonons. Contributions of the confined phonon (with built-in electric field) become larger, whereas those of the interface and half-space phonons become smaller, and the total contribution of phonons also have obvious change. Contributions of these optical phonons to the ground state energies and binding energies of the bound polarons in In0.19Ga0.81N/GaN quantum wells are larger than the corre-sponding values (about 3.1-1.6 meV and 1.5-0.3 meV) of those in GaAs/Al0.19Ga0.81As quantum wells. The binding energies in In0.19Ga0.81N/GaN quantum wells decrease monotonically with increasing location Z0 of the impurity center for a constant well width d = 8 nm, and the decrease of speed becomes faster. As the position of the impurity center is increasing, the contributions of the the interface and half-space phonons decrease slowly, and those of the confined phonons increase slowly as well.关键词
束缚极化子/结合能/量子阱/内建电场Key words
bound polaron/binding energy/quantum well/built-in electric field引用本文复制引用
赵凤岐,张敏,李志强,姬延明..纤锌矿In0.19Ga0.81N/GaN量子阱中光学声子和内建电场对束缚极化子结合能的影响[J].物理学报,2014,(17):1-8,8.基金项目
国家自然科学基金(批准号:10964007,11264027)、内蒙古“草原英才”工程和内蒙古师范大学“十百千”人才培养工程基金(批准号:RCPY-2-2012-K-039)资助的课题 （批准号:10964007,11264027）
