Kenji Yoshida, K. Shibata, K. Hirakawa
Aug 1, 2015
2015 40th International Conference on Infrared, Millimeter, and Terahertz waves (IRMMW-THz)
We have investigated the electron transport in single C60 molecule transistors under the illumination of intense monochromatic terahertz (THz) radiation. By employing an antenna structure with a sub-nm wide gap, we concentrate the THz radiation beyond the diffraction limit and focus it onto a single molecule. The photon-assisted tunneling (PAT) in the single molecule transistors has been observed both in the weak-coupling and Kondo regimes. The THz power dependence of the PAT conductance indicates that, when the incident THz intensity is a few tens mW, the THz field induced at the molecule exceeds 100 kV/cm, which is enhanced by a factor of ~105 from the field in the free space.