Zhang Weidong, Pham Phi H Q, Brown Elliott R, Burke Peter J
Terahertz Sensors Laboratory, Departments of Physics and Electrical Engineering, Wright State University, Dayton, OH 45435, USA.
Nanoscale. 2014 Nov 21;6(22):13895-9. doi: 10.1039/c4nr03222e.
THz frequency-domain transmittance measurements were carried out on chemical-vapor-deposited (CVD) graphene films transferred to high-resistivity silicon substrates, and packaged as back-gated graphene field effect transistors (G-FETs). The graphene AC conductivity σ(ω), both real and imaginary parts, is determined between 0.2 and 1.2 THz from the transmittance using the transmission matrix method and curve-fitting techniques. Critical parameters such as the charge-impurity scattering width and chemical potential are calculated. It is found that not only the sheet charge density but also the scattering parameter can be modified by the back-gate voltage.
对转移到高电阻率硅衬底上并封装为背栅石墨烯场效应晶体管（G-FET）的化学气相沉积（CVD）石墨烯薄膜进行了太赫兹频域透射率测量。利用传输矩阵法和曲线拟合技术，根据透射率在0.2至1.2太赫兹之间确定了石墨烯的交流电导率σ(ω)的实部和虚部。计算了诸如电荷杂质散射宽度和化学势等关键参数。研究发现，背栅电压不仅可以改变面电荷密度，还可以改变散射参数。
