Abstract
We demonstrate terahertz (THz) imaging and spectroscopy of a 15 × 15-mm2 single-layer graphene film on Si using broadband THz pulses. The THz images clearly map out the THz carrier dynamics of the grapheneon-Si sample, allowing us to measure sheet conductivity with sub-mm resolution without fabricating electrodes. The THz carrier dynamics are dominated by intraband transitions and the THz-induced electron motion is characterized by a flat spectral response. A theoretical analysis based on the Fresnel coefficients for a metallic thin film shows that the local sheet conductivity varies across the sample from σs = 1.7 × 10--3 to 2.4 × 10 -3 Ω-1 (sheet resistance, ρs = 420 - 590 Ω/sq).
Original language | English (US) |
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Pages (from-to) | 141-146 |
Number of pages | 6 |
Journal | Optics Express |
Volume | 19 |
Issue number | 1 |
DOIs | |
State | Published - Jan 3 2011 |
Externally published | Yes |
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics