Femtosecond relaxation dynamics of Tamm plasmon-polaritons (Conference Presentation)

Abstract

Tamm plasmon-polariton (TPP) is an optical analogue of Tamm state and appears as spatial localization of the electromagnetic field near the boundary of one-dimensional photonic crystal (PC) (distributed Bragg reflector) and a metal film. TPP can be detected experimentally as a narrow resonance in the reflectance or transmittance spectrum of a PC/metal structure. Contrary to surface plasmon-polariton TPP occurs at any angles of incident light for both TE and TM polarizations, and it excitation does not require sophisticated optical schemes (such as Kretchmann scheme). The peculiarities of TPP optical properties led to considerable interest to the design, fabrication and study of TPP-supported structures in the past several years. In present work, the ultrafast relaxation dynamics of TPP excited in the PC/metal structures is measured using intensity cross-correlation scheme. The TPP lifetime is obtained for different polarizations and incident angles of light, and compared with one obtained from numerical calculations. A femtosecond pulse reflected from such a structure is found to be significantly distorted if its spectrum overlaps with the TPP resonance. The TPP lifetime possesses strong polarization and angular dependence and is shown to vary from 20 fs for p-polarized light to 40 fs for s-polarized light at a 45◦ angle of incidence. The reported lifetime of TPP is several times smaller than the previously reported lifetime of surface plasmons. Short lifetime and sharpness of resonance make TPP a good candidate for use in all-optical switches and modulators.