IBM Research-Zurich, Säumerstrasse 4, 8803 Rüschlikon, Switzerland.
Nat Commun. 2014 Dec 16;5:5837. doi: 10.1038/ncomms6837.
Stacking fault defects are thought to be the root cause for many of the anomalous transport phenomena seen in high-quality graphite samples. In stark contrast to their importance, direct observation of stacking faults by diffractive techniques has remained elusive due to fundamental experimental difficulties. Here we show that the stacking fault density and resistance can be measured by analyzing the non-Gaussian scatter observed in the c-axis resistivity of mesoscopic graphite structures. We also show that the deviation from Ohmic conduction seen at high electrical field strength can be fit to a thermally activated transport model, which accurately reproduces the stacking fault density inferred from the statistical analysis. From our measurements, we conclude that the c-axis resistivity is entirely determined by the stacking fault resistance, which is orders of magnitude larger than the inter-layer resistance expected from a Drude model.
堆垛层错缺陷被认为是许多高质量石墨样品中异常输运现象的根本原因。与它们的重要性形成鲜明对比的是，由于基本的实验困难，通过衍射技术直接观察堆垛层错仍然难以实现。在这里，我们通过分析介观石墨结构中 c 轴电阻率的非高斯散射，表明可以通过分析非高斯散射来测量堆垛层错密度和电阻。我们还表明，在高电场强度下观察到的偏离欧姆传导可以拟合到热激活输运模型中，该模型准确地再现了从统计分析中推断出的堆垛层错密度。从我们的测量结果可以得出结论，c 轴电阻率完全由堆垛层错电阻决定，其电阻比德拜模型所预期的层间电阻大几个数量级。
