Probing Charged Impurities in Suspended Graphene Using Raman Spectroscopy
- 3 March 2009
- journal article
- research article
- Published by American Chemical Society (ACS) in ACS Nano
- Vol. 3 (3), 569-574
- https://doi.org/10.1021/nn900130g
Abstract
Charged impurity (CI) scattering is one of the dominant factors that affects the carrier mobility in graphene. In this paper, we use Raman spectroscopy to probe the charged impurities in suspended graphene. We find that the 2D band intensity is very sensitive to the CI concentration in graphene, while the G band intensity is not affected. The intensity ratio between the 2D and G bands, I2D/IG, of suspended graphene is much stronger compared to that of nonsuspended graphene, due to the extremely low CI concentration in the former. This finding is consistent with the ultrahigh carrier mobility in suspended graphene observed in recent transport measurements. Our results also suggest that at low CI concentrations that are critical for device applications, the I2D/IG ratio is a better criterion in selecting high quality single layer graphene samples than is the G band blue shift.Keywords
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This publication has 30 references indexed in Scilit:
- Approaching ballistic transport in suspended grapheneNature Nanotechnology, 2008
- Measurement of the Elastic Properties and Intrinsic Strength of Monolayer GrapheneScience, 2008
- Macroscopic Graphene Membranes and Their Extraordinary StiffnessNano Letters, 2008
- Charged-impurity scattering in grapheneNature Physics, 2008
- Superior Thermal Conductivity of Single-Layer GrapheneNano Letters, 2008
- Measurement of Scattering Rate and Minimum Conductivity in GraphenePhysical Review Letters, 2007
- Effect of inelastic collisions on multiphonon Raman scattering in graphenePhysical Review B, 2007
- Carrier Transport in Two-Dimensional Graphene LayersPhysical Review Letters, 2007
- Electric Field Effect Tuning of Electron-Phonon Coupling in GraphenePhysical Review Letters, 2007
- Raman Spectrum of Graphene and Graphene LayersPhysical Review Letters, 2006