(AIP Publishing, 2015) Khromova, Irina; Navarro Cía, Miguel; Brener, I.; Reno, J. L.; Ponomarev, A.; Mitrofanov, Oleg; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
We observe dipole resonances in thin conductive carbon micro-fibers by detecting an enhanced
electric field in the near-field of a single fiber at terahertz (THz) frequencies. Time-domain analysis
of the electric field shows that each fiber sustains resonant current oscillations at the frequency
defined by the fiber’s length. Strong dependence of the observed resonance frequency and degree
of field enhancement on the fibers’ conductive properties enable direct non-contact probing of the
THz conductivity in single carbon micro-fibers. We find the conductivity of the fibers to be within
the range of 1–5 10 4 S/m. This approach is suitable for experimental characterization of individual
doped semiconductor resonators for THz metamaterials and devices.