[15p-B6-1~16] 17.2 Graphene

[15p-B6-11] Temperature and Substrate Dependences of Optical Conductivities of Graphene Measured by Terahertz Time Domain Spectroscopy

〇Iwao Kawayama¹, Shohei Kameo¹, Shinya Kawano¹, Filchito Renee Bagsican¹, Hironaru Murakami¹, Junichiro Kono^1,2, Robert Vajtai², Pulickel Ajayan², Masayoshi Tonouchi¹ (1.Osaka Univ., 2.Rice Univ.)

Keywords:graphene, THz spectroscopy, temperature dependence

Graphene is extremely susceptible to perturbations from its environment, and the studies with graphene have shown the strong influence of the supporting substrate and the local molecular environment on the optical and DC transport properties of graphene. However, no systematic studies have been done on the effects of temperature, substrates, and gas adsorption on the terahertz (THz) properties of graphene. In this study, we measured the temperature-dependence of the THz conductivity of graphene deposited on Si, MgO and SiO₂ substrates in the temperature range from 80K to 600 K. We found that the THz conductivity shows qualitatively different behaviors depending on the substrates. We observed that the effect of adsorbed gas molecules on the THz conductivity also varies depending on the substrates.