Terahertz time-domain measurement of non-Drude conductivity in silver nanowire thin films for transparent electrode applications

Abstract

We have investigated the complex conductivity of silver nanowire thin films using terahertz time-domain spectroscopy. Maxwell-Garnett effective medium theory, which accounts for the effective complex conductivity of silver nanowires, is presented in detail theoretically and experimentally. The conductivity of nanowires exhibits a characteristic non-Drude response in which the applied terahertz field is polarized in the longitudinal nanowire direction. The non-Drude responses of the silver nanowires are explained by the Gans approximation and the Drude-Smith model, and both agree well with the experimental data. Our results provide a basis for further explorations of charge carrier dynamics in nanowire-based transparent electrode applications.

Electrical characterization of silver nanowire-graphene hybrid films from terahertz transmission and reflection measurements

“…These collisions certainly occur at the surface of the nanowires as the carrier mean-free path is of the order of the nanowires diameter. 8 The quite small sheet conductivity in these films, as compared to GRP, is due to a smaller charge carrier density in AgNW-GRP.…”

“…5 Silver nanowires (AgNWs) are flexible materials with excellent electrical conductivity. [6][7][8] Recently, new AgNW-GRP transparent conducting hybrid films have been intensively investigated in view of the developing of DNA sensor, 9 biological, 10 and optoelectronic devices. 11 A comprehensive knowledge of the electrical conduction in GRP and AgNW-GRP hybrid films, as well as a precise measurement of their optical and electrical parameters, is compulsory for designing optimized electronic components.…”

Terahertz time-domain measurement of non-Drude conductivity in silver nanowire thin films

“…A wide range of applications using transparent thin-film electrodes emerge in areas such as liquid crystal displays (LCDs), organic light-emitting diodes (OLEDs), touch screens, and solar cells. Metallic nanowires, especially silver nanowires (Ag NWs), are considered to be good candidates for these applications, since Ag NWs exhibit outstanding electrical conductivity as well as high mechanical flexibility due to the mesh-like network structures mixed with various composites [1][2][3]. Therefore, it is important to explore the electromagnetic response of the NWbased transparent thin films.…”

“…Therefore, it is important to explore the electromagnetic response of the NWbased transparent thin films. Terahertz time domain spectroscopy (THz-TDS) is an excellent spectroscopic tool for measuring conductivity without requiring electrical contact or damage to the samples [3].In this work, we study spectroscopic measurements on the terahertz (THz) complex conductivity of transparent metal composites containing various filling fractions of Ag NWs (1-15%) (Figs. 1a and b).…”

“…Therefore, it is important to explore the electromagnetic response of the NWbased transparent thin films. Terahertz time domain spectroscopy (THz-TDS) is an excellent spectroscopic tool for measuring conductivity without requiring electrical contact or damage to the samples [3].…”