,First-Principles Calculations Of Electronic Structures of New Ⅲ-Ⅴ Semiconductors: BxGa1-x As and Tl

• 作 者: ZHOU Jing REN Xiao-Min HUANG Yong-Qing WANG Qi HUANG Hui
• 机 构: Key Laboratory of Optical Communication and Lightwave Technologies Ministry of Education, Beijing Un
• 出 处: 中国物理快报（英文版）
• 发表日期: 2008年9期

We investigate the electronic structures of new semiconductor alloys BxGa1-x As and Tlx Ga1-x As, employing first-principles calculations within the density-functional theory and the generalized gradient approximation.The calculation results indicate that alloying a small Tl content with GaAs will produce larger modifications of the band structures compared to B. A careful investigation of the inteal lattice structure relaxation shows that significant bond-length relaxations takes place in both the alloys, and it tus out that difference between the band-gap bowing behaviours for B and Tl stems from the different impact of atomic relaxation on the electronic structure. The relaxed structure yields electronic-structure results, which are in good agreement with the experimental data. Finally, a comparison of formation enthalpies indicates that the production Tlx Ga1-x As with Tl concentration of at least 8% is possible.