Abstract
We determine the quantum scattering time τq in six graphene samples with mobility of 4400<μ<17000 cm2 /Vs over a wide range of carrier density (1.2<n<6× 1012 / cm2). τq derived from Shubnikov-de Haas oscillation ranges ∼25-74fs, corresponding to a single-particle level broadening of 4.5-13 meV. The ratio of the transport to quantum scattering time τt / τq spans 1.5-5.1 in these samples, which can be quantitatively understood combining scattering from short-ranged centers and charged impurities located within 2 nm of the graphene sheet. Our results suggest that charges residing on the SiO2 surface play a dominant role in limiting carrier mobility in current samples.
| Original language | English (US) |
|---|---|
| Article number | 241415 |
| Journal | Physical Review B - Condensed Matter and Materials Physics |
| Volume | 80 |
| Issue number | 24 |
| DOIs | |
| State | Published - Dec 29 2009 |
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics