Time-domain measurements of surface plasmon polaritons in the terahertz frequency range

Abstract

We present time domain measurements of surface-plasmon polaritons (SPP's) at terahertz (THz) frequencies. SPP's are generated by coupling THz radiation into dielectric films deposited on flat gold surfaces. In this way we are able to perform very sensitive and broadband THz measurements of thin dielectric films, demonstrating the capabilities of SPP's for $\mathrm{Thz}$ thin film spectroscopy. By varying the thickness of these films we observe drastic changes in the field distribution of the SPP's.