【摘要】 利用基于密度泛函理论的平面波超软赝势法研究了对16个原子的BenZn8-nO8和Mg1BenZn7-nO8超胞进行了几何结构优化,计算了总能。从理论上给出了BeO的能带结构、态密度;BexZn1-xO合金的晶格常数、能带弯曲系数,差分电荷密度;BexZn1-xO合金的稳定性以及Mg掺杂BexZn1-xO合金的特性。计算结果表明:BexZn1-xO合金非常稳定;晶体结构参数与实验相符,并基本符合Vegard’s law(维加德定律);能带弯曲系数非常大(5.6eV左右);掺入适量的Mg原子不仅可以解决晶格失配问题、增大band off-set(能带偏移),还可以提高BexZn1-xO合金的稳定性;Be原子成为间隙杂质的可能性很小。BexZn1-xO合金可以作为ZnO/MgxZn1-xO超晶格和量子阱的最佳材料。更多还原

【Abstract】 The geometry structure of 16-atom supercell of BenZn8-nO8 and Mg1BenZn7-nO8 was optimized by adopting the method of ultra-soft pseudopotential technology of total energy-plane wave based upon the density functional theory(DFT).Cell parameters and total energys were calculated.Band structures and partial density of states of BeO, lattice parameters and stability of BexZn1-xO and Mg-doped BexZn1-xO alloys,energy bowing parameters of BexZn1-xO are calculated and analyzed.The results indicated that the structure of BexZn1-xO alloys are very stable,calculated lattice parameters are consist with experimental results,and also close to Vegard’s law,the calculated bandgap bowing parameter is as large as 5.6eV.It is also revealed that the problem of lattice mismatch can be solved,the band off-set can be increased,and the stability of BexZn1-xO alloys can be increased by dopping a little amount of Mg atoms.更多还原