R. van Gelderen, R. Olsen, C. Morais Smith
In this article we study the static polarization in ABC-stacked multilayer graphene. Since the density of states diverges for these systems if the number of layers exceeds three, screening effects are expected to be important. In the random phase approximation, screening can be included through the polarization. We derive an analytical integral expression for the polarization in both the full-band model and an effective two-band model. Numerical evaluation of these integrals are very time consuming in the full-band model. Hence, for ABC-stacked trilayer graphene, we use the two-band model to calculate the low momentum part of the polarization. The high momentum part is linear and is determined by calculating two points, such that we can determine the slope. The numerical results for the polarization of trilayer graphene are used to sketch the screened potential.
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http://arxiv.org/abs/1304.5501
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