Nearest-neighbor configuration in (GaIn)(NAs) probed by x-ray absorption spectroscopy.
Nearest-neighbor configuration in (GaIn)(NAs) probed by x-ray absorption spectroscopy.
复制标题
通过 X 射线吸收光谱探测 (GaIn)(NAs) 中的最近邻构型。
DOI：
10.1103/physrevlett.90.145505
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发表时间：
2003
影响因子：
8.6
通讯作者：
J. Harris
中科院分区：
文献类型：
--
作者：
V. Lordi;V. Gambin;S. Friedrich;T. Funk;T. Takizawa;K. Uno;J. Harris
Ga(1-x)In(x)N(y)As(1-y)是一种有前途的材料系统，用于制造廉价的“最后一英里”光电元件。然而，其原子排列的细节以及与观察到的光学性质的关系尚不完全清楚。特别地，在退火后观察到发射波长的蓝移。在这项工作中，我们利用X射线吸收精细结构来研究材料中退火前后N原子周围的化学环境。我们发现生长的分子束外延材料由几乎随机分布的原子组成，而退火后的材料显示出 In 向 N 的偏析。从头算模拟表明，这种短程有序产生了热力学更稳定的合金，并导致发射蓝移。
Ga(1-x)In(x)N(y)As(1-y) is a promising material system for the fabrication of inexpensive "last-mile" optoelectronic components. However, details of its atomic arrangement and the relationship to observed optical properties is not fully known. Particularly, a blueshift of emission wavelength is observed after annealing. In this work, we use x-ray absorption fine structure to study the chemical environment around N atoms in the material before and after annealing. We find that as-grown molecular beam epitaxy material consists of a nearly random distribution of atoms, while postannealed material shows segregation of In toward N. Ab initio simulations show that this short-range ordering creates a more thermodynamically stable alloy and is responsible for blueshifting the emission.