Mapping the surface phase diagram of GaAs(001) using droplet epitaxy
Mapping the surface phase diagram of GaAs(001) using droplet epitaxy
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DOI：
10.1103/physrevmaterials.3.124603
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发表时间：
2019-12
影响因子：
3.4
通讯作者：
C. Zheng;K. Hannikainen;Y. Niu;J. Tersoff;D. Gomez;J. Pereiro;D. Jesson
中科院分区：
文献类型：
--
作者：
C. Zheng;K. Hannikainen;Y. Niu;J. Tersoff;D. Gomez;J. Pereiro;D. Jesson
我们将液滴外延和低能电子显微镜成像技术相结合，绘制出了GaAs(001)的表面相图。用一个简单的模型解释了液滴外延过程中产生的相图，该模型将相界面的空间坐标与自由能联系起来。因此，根据观察到的远离液滴边缘的相的顺序，可以获得关于表面相稳定性的重要信息。这可以用来扩充现有的由密度泛函理论计算产生的T=0K相图。我们证明了(3×6)相的存在，并证实了有争议的(6×6)相在很小的化学势范围内是热力学稳定的。
We combine droplet epitaxy with low-energy electron microscopy imaging techniques to map the surface phase diagram of GaAs(001). The phase patterns produced in droplet epitaxy are interpreted using a simple model which links the spatial coordinates of phase boundaries to the free energy. It is thereby possible to gain important information on surface phase stability, based on the observed sequential order of the phases away from the droplet edge. This can be used to augment existing T=0K phase diagrams generated by density-functional theory calculations. We establish the existence of a (3×6) phase, and confirm that the controversial (6×6) phase is thermodynamically stable over a narrow range of chemical potential.