Whelan Patrick R, Iwaszczuk Krzysztof, Wang Ruizhi, Hofmann Stephan, Bøggild Peter, Jepsen Peter Uhd
Opt Express. 2017 Feb 6;25(3):2725-2732. doi: 10.1364/OE.25.002725.
We demonstrate a method for reliably determining the electrical properties of graphene including the carrier scattering time and carrier drift mobility from terahertz time- domain spectroscopy measurements (THz-TDS). By comparing transients originating from directly transmitted pulses and the echoes from internal reflections in a substrate, we are able to extract electrical properties irrespective of random time delays between pulses emitted in a THz-TDS setup. If such time delays are not accounted for they can significantly influence the extracted properties of the material. The technique is useful for a robust determination of electrical properties from THz-TDS measurements and is compatible with substrate materials where transients from internal reflections are well-separated in time.
我们展示了一种从太赫兹时域光谱测量(THz-TDS)中可靠地确定石墨烯电学性质的方法,包括载流子散射时间和载流子漂移迁移率。通过比较直接传输脉冲产生的瞬态信号和衬底内部反射产生的回波,我们能够提取电学性质,而不受THz-TDS装置中发射脉冲之间随机时间延迟的影响。如果不考虑这种时间延迟,它们会显著影响所提取的材料性质。该技术对于从THz-TDS测量中稳健地确定电学性质很有用,并且与内部反射瞬态信号在时间上能很好分离的衬底材料兼容。