Interstitial oxygen in germanium and silicon
Interstitial oxygen in germanium and silicon
复制标题
锗和硅中的间隙氧
DOI：
10.1103/physrevb.56.3820
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发表时间：
1997
影响因子：
3.7
通讯作者：
E. Haller
中科院分区：
文献类型：
--
作者：
E. Artacho;F. Yndurain;B. Pajot;R. Ramírez;C. Herrero;L. Khirunenko;K. Itoh;E. Haller
从实验和理论上研究了锗中间隙氧的微观结构及其相关动力学。红外吸收光谱是使用基于描述核运动势能的第一原理总能量计算的动态矩阵模型来计算的。计算光谱特征和同位素位移并与可用的实验结果进行比较。从天然和准同位素锗样品的新光谱数据中，获得了新的同位素位移并与理论预测进行了比较。低能谱根据受阻转子模型进行分析。实现了对中心的公平理解，然后将其与硅中的间隙氧进行比较。氧原子在硅和锗中都存在非平凡的量子离域，但物理性质却截然不同：Si-O-Si 准分子本质上是线性的，而 Ge-O-Ge 结构是褶皱的。使用路径积分蒙特卡罗模拟解决了硅中氧的高度非谐波势阱中的离域，并与锗中的氧旋转进行比较。通过这些新信息获得的理解使我们能够解释两个系统在红外和远红外光谱区域之间的显着差异，以及对隐藏振动模式存在的预测，这些振动模式从未在实验中直接观察到，但得到同位素位移分析的充分支持。 {版权} {ital 1997} {ital 美国物理学会}« 更少
The microscopic structure of interstitial oxygen in germanium and its associated dynamics are studied both experimentally and theoretically. The infrared absorption spectrum is calculated with a dynamical matrix model based on first-principles total-energy calculations describing the potential energy for the nuclear motions. Spectral features and isotope shifts are calculated and compared with available experimental results. From new spectroscopic data on natural and on quasimonoisotopic germanium samples, new isotope shifts have been obtained and compared with the theoretical predictions. The low-energy spectrum is analyzed in terms of a hindered rotor model. A fair understanding of the center is achieved, which is then compared with interstitial oxygen in silicon. The oxygen atom is nontrivially quantum delocalized both in silicon and in germanium, but the physics is shown to be very different: while the Si-O-Si quasimolecule is essentially linear, the Ge-O-Ge structure is puckered. The delocalization in a highly anharmonic potential well of oxygen in silicon is addressed using path-integral Monte Carlo simulations, for comparison with the oxygen rotation in germanium. The understanding achieved with this new information allows us to explain the striking differences between both systems, in both the infrared and the far-infrared spectral regions, and the prediction of the existencemore » of hidden vibrational modes, never directly observed experimentally, but soundly supported by the isotope-shift analysis. {copyright} {ital 1997} {ital The American Physical Society}« less