Nonlinear optical absorption and asymmetric charge carrier conduction in chemical vapor deposited single-layer graphene

Abstract

In this work, we report the nonlinear optical absorption and asymmetric charge carrier conduction in single layer graphene films deposited by chemical vapor deposition (CVD) technique on copper foils with pretreated surface. XRD texture and pole figure analysis of the substrate are utilized for the visualization of the effect of the pretreatment on the substrate. The synthesised graphene is employed as a channel layer in a back gated field-effect transistor and the asymmetric behavior of charge carriers is analyzed. Nonlinear optical response of graphene is recorded after transferring it onto a quartz substrate. Open aperture Z-scan technique yields a nonlinear absorption coefficient of 5.34×10 6 cm GW −1 . The film exhibits saturable absorption in the visible range with a saturation intensity as low as 0.134 GW cm −2 .

Chemical vapour deposited graphene-mediated enhanced SERS performance in silver nanostructures

“…Hydrogen and argon were the other two gases that supported the growth. The optimal growth parameters are described in detail elsewhere [21,22]. The Raman spectra of graphene grown on copper foils were recorded using Horiba's LabRAM HR micro-Raman spectrometer.…”

“…In the first step of GSERS substrate fabrication, graphene was transferred from copper foil to 300 nm covered wafer ( ). The different steps elucidated by Thomas et al were followed in this process [22]. Leica DFC 280 microscope and ZEISS Sigma microscope were used to record the optical and the field emission scanning electron microscopic (FESEM) images, respectively.…”