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arXiv · 0910.0185

Infrared spectroscopic studies on unoriented single-walled carbon nanotube films under hydrostatic pressure

K. Thirunavukkuarasu·F. Hennrich·K. Kamarás·C. A. Kuntscher
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Abstract

The electronic properties of as-prepared and purified unoriented single-walled carbon nanotube films were studied by transmission measurements over a broad frequency range (far-infrared up to visible) as a function of temperature (15 K - 295 K) and external pressure (up to 8 GPa). Both the as-prepared and the purified SWCNT films exhibit nearly temperature-independent properties. With increasing pressure the low-energy absorbance decreases suggesting an increasing carrier localization due to pressure-induced deformations. The energy of the optical transitions in the SWCNTs decreases with increasing pressure, which can be attributed to pressure-induced hybridization and symmetry-breaking effects. We find an anomaly in the pressure-induced shift of the optical transitions at $\sim$2 GPa due to a structural phase transition.

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K. Thirunavukkuarasu, F. Hennrich, K. Kamarás, C. A. Kuntscher. 2009-10-01. Infrared spectroscopic studies on unoriented single-walled carbon nanotube films under hydrostatic pressure. https://doi.org/10.1103/physrevb.81.045424

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