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arXiv · 1603.06365

Influence of rhombohedral stacking order in the electrical resistance of bulk and mesoscopic graphite

M. Zoraghi·J. Barzola-Quiquia·M. Stiller·A. Setzer·P. Esquinazi·G. H. Kloess·T. Muenster·T. Lühmann·I. Estrela-Lopis
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Abstract

The electrical, in-plane resistance as a function of temperature $R(T)$ of bulk and mesoscopic thin graphite flakes obtained from the same batch was investigated. Samples thicker than $\sim 30$ nm show metalliclike contribution in a temperature range that increases with the sample thickness, whereas a semiconductinglike behavior was observed for thinner samples. The temperature dependence of the in-plane resistance of all measured samples and several others from literature can be very well explained between 2 K and 1100 K assuming three contributions in parallel: a metalliclike conducting path at the interfaces between crystalline regions, composed of two semiconducting phases, i.e. Bernal and rhombohedral stacking. From the fits of $R(T)$ we obtain a semiconducting energy gap of $110 \pm 20$meV for the rhombohedral and $38\pm 8 $meV for the Bernal phase. The presence of these crystalline phases was confirmed by x-ray diffraction measurements. We review similar experimental data from literature of the last 33 years and two more theoretical models used to fit $R(T)$.

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M. Zoraghi, J. Barzola-Quiquia, M. Stiller, A. Setzer, P. Esquinazi, G. H. Kloess, T. Muenster, T. Lühmann, I. Estrela-Lopis. 2016-03-21. Influence of rhombohedral stacking order in the electrical resistance of bulk and mesoscopic graphite. https://doi.org/10.1103/physrevb.95.045308

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