Buffer layer limited conductivity in epitaxial graphene on the Si face of SiC
Buffer layer limited conductivity in epitaxial graphene on the Si face of SiC
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DOI：
10.1103/physrevb.86.125426
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发表时间：
2012-09
影响因子：
3.7
通讯作者：
S. Shallcross;S. Hensel;O. Pankratov
中科院分区：
文献类型：
--
作者：
S. Shallcross;S. Hensel;O. Pankratov
我们描述了一种机制，其中SiC/石墨烯界面的低能声子改变缓冲层和石墨烯覆盖层之间的分离，导致变形势和电荷载流子散射。我们首先确定这种变形势，然后计算玻尔兹曼形式下的输运性质。我们的研究结果表明(i) Dirac点附近的电阻率随着温度的升高而显著降低（），（ii） Dirac点附近的电阻率呈线性增加，（iii） SiC Si表面外延石墨烯的电阻率在低温到室温之间的变化与实验结果很好地吻合。
We describe a mechanism in which low-energy phonons of the SiC/graphene interface modify the separation between the buffer layer and the graphene overlayer, resulting in a deformation potential and hence charge carrier scattering. We determine this deformation potentialab initio, and then calculate transport properties within the Boltzmann formalism. Our results show (i) a remarkable decrease in the resistivity () near the Dirac point with increasing temperature (), (ii) a linear increase ofwithaway from the Dirac point, and (iii) good agreement with experiment for low temperature to room temperature change in resistivity for epitaxial graphene on the SiC Si face.