Electronic transport in graphene : A semiclassical approach including midgap states
Electronic transport in graphene : A semiclassical approach including midgap states
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DOI：
10.1103/physrevb.76.205423
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发表时间：
2007-07
影响因子：
3.7
通讯作者：
T. Stauber;N. Peres;F. Guinea
中科院分区：
文献类型：
--
作者：
T. Stauber;N. Peres;F. Guinea
利用半经典玻尔兹曼理论，计算了电导率随载流子密度的变化。通常，我们包括从带电杂质的散射，但得出的结论是，估计的杂质密度太低，以解释实验观察到的迁移率。因此，我们提出了一个额外的散射机制，涉及midgap状态，导致类似的k-依赖性的弛豫时间带电杂质。新的散射机制可以解释实验结果，如电导率与栅极电压的亚线性行为和清洁样品的最小电导率的增加。我们还讨论了温度依赖的散射由于声学声子。
Using the semi-classical Boltzmann theory, we calculate the conductivity as function of the carrier density. As usually, we include the scattering from charged impurities, but conclude that the estimated impurity density is too low in order to explain the experimentally observed mobilities. We thus propose an additional scattering mechanism involving midgap states which leads to a similar k-dependence of the relaxation time as charged impurities. The new scattering mechanism can account for the experimental findings such as the sublinear behavior of the conductivity versus gate voltage and the increase of the minimal conductivity for clean samples. We also discuss temperature dependent scattering due to acoustic phonons.