有限厚势垒量子阱中杂质态结合能

利用变分法对有限厚势垒GaAs/AlxGa1-xAs量子阱结构中杂质态结合能进行数值计算,给出杂质态结合能随阱宽、垒厚和杂质位置的变化关系,且与无限厚势垒情形进行比较.结果表明,有限厚势垒杂质态结合能明显小于无限厚势垒情形.同时,在中间阱宽时,这两种情形的杂质态结合能差别最大,在宽阱时,差别最小.此外,还考虑电子有效质量、材料介电常数及禁带宽度随流体静压力变化对杂质态结合能的影响.

Binding Energies of Impurity States in Quantum Wells with Finite Thick Potential Barriers

A variational method is adopted to investigate the binding energies of impurity states in GaAs/AlxGa1-xAs quantum wells with finite thick potential barriers.The relations between binding energies of impurity states and well width,barrier thickness and impurity position are given and compared with that of quantum wells with infinite thick barriers.The results indicate that the binding energy for a quantum well with finite thick barriers is obviously less than that one with infinite thick barriers.Meanwhile,the difference of the binding energies of impurity states for the above cases is maximum when the well is intermediate wide,whereas the difference is minimum for a wide well.Moreover,the influences on the binding energy are also discussed by considering the variations of the electron effective mass,dielectric constant,and conduction band offset between the well and barriers with hydrostatic pressure.