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arXiv · 1101.1338

Terahertz imaging and spectroscopy of large-area single-layer graphene

J. L. Tomaino·A. D. Jameson·J. W. Kevek·M. J. Paul·A. M. van der Zande·R. A. Barton·P. L. McEuen·E. D. Minot·Yun-Shik Lee
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Abstract

We demonstrate terahertz (THz) imaging and spectroscopy of a 15x15-mm^2 single-layer graphene film on Si using broadband THz pulses. The THz images clearly map out the THz carrier dynamics of the graphene-on-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 {\sigma}s = 1.7x10^-3 to 2.4x10^-3 {\Omega}^-1 (sheet resistance, {\rho}s = 420 - 590 {\Omega}/sq).

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J. L. Tomaino, A. D. Jameson, J. W. Kevek, M. J. Paul, A. M. van der Zande, R. A. Barton, P. L. McEuen, E. D. Minot, Yun-Shik Lee. 2011-01-07. Terahertz imaging and spectroscopy of large-area single-layer graphene. https://doi.org/10.1364/oe.19.000141

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