石墨烯中散射率和最小电导率的测量。

Measurement of scattering rate and minimum conductivity in graphene.

作者信息

Tan Y-W, Zhang Y, Bolotin K, Zhao Y, Adam S, Hwang E H, Das Sarma S, Stormer H L, Kim P

机构信息

Department of Physics, Columbia University, New York, New York 10027, USA.

出版信息

Phys Rev Lett. 2007 Dec 14;99(24):246803. doi: 10.1103/PhysRevLett.99.246803.

DOI:10.1103/PhysRevLett.99.246803

PMID:18233473

Abstract

The conductivity of graphene samples with various levels of disorder is investigated for a set of specimens with mobility in the range of 1-20x10(3) cm2/V sec. Comparing the experimental data with the theoretical transport calculations based on charged impurity scattering, we estimate that the impurity concentration in the samples varies from 2-15x10(11) cm(-2). In the low carrier density limit, the conductivity exhibits values in the range of 2-12e2/h, which can be related to the residual density induced by the inhomogeneous charge distribution in the samples. The shape of the conductivity curves indicates that high mobility samples contain some short-range disorder whereas low mobility samples are dominated by long-range scatterers.

摘要

对于一组迁移率在1 - 20×10³ cm²/V·sec范围内的石墨烯样品，研究了不同无序程度下的电导率。将实验数据与基于带电杂质散射的理论输运计算进行比较，我们估计样品中的杂质浓度在2 - 15×10¹¹ cm⁻²之间变化。在低载流子密度极限下，电导率呈现出2 - 12e²/h的数值范围，这可能与样品中不均匀电荷分布引起的残余密度有关。电导率曲线的形状表明，高迁移率样品包含一些短程无序，而低迁移率样品则以长程散射体为主。