Terahertz Detection as a Probe of Luttinger-Liquid Behavior in an Individual Single-Walled Carbon Nanotube

Carbon nanotubes (CNTs) serve as an experimental system for verification of physical models of one-dimensional (1-D) conduction, in particular the Luttinger-liquid theory. We describe measurements of terahertz (THz) absorption in individual single-walled carbon nanotubes and distinguish between two response mechanisms: bolometric detection due to heating a CNT with a temperature-dependent resistance and the response due to non-thermal electrical contact nonlinearities. The effect of the contact nonlinearity is not significantly decreased at THz frequencies, allowing for analysis of the parallel contact capacitance to an individual CNT.[1] We study high-frequency charge excitations in a CNT as a probe of the strength of the electron-electron interactions due to the lack of screening in this 1-D system. This is achieved by exciting terahertz standing wave resonances along the length of a CNT, observed using the nonlinear detection mechanism. We exploit this experimental technique to test predictions of the Luttinger-liquid model. $\backslash \backslash $[4pt] [1] J.D. Chudow, D.F. Santavicca, C.B. McKitterick, D.E. Prober and P. Kim, \textit{Appl. Phys. Lett.} \textbf{100}, 163503 (2012).