Results in Physics
Topological insulator, Surface plasmon resonance, Plasmons (Physics)
Axion electrodynamics is applied to study the response of a plasmonic nanoshell with a core made of topological insulator (TI) materials. The electric polarizability of such a system is calculated in the long wavelength limit via the introduction of two scalar potentials satisfying the various appropriate boundary conditions. Our focus is on the topological magneto-electric effect (TME) as manifested in the coupled plasmonic resonances of the nanoshell. It is found that for a TI with broken time-reversal symmetry, such TME will lead to observable red-shifts in the coupled plasmonic modes, with more significant manifestation of such shifts for the bonding modes of a metallic nanoshell. It is speculated that such universal red-shift could be a manifestation of the fundamental dual symmetry as generalized for axion electrodynamics.
Locate the Document
Chang, R., Xie, H. Y., Wang, Y. C., Chiang, H. P., & Leung, P. T. (2019). Topological magnetoelectric effect as probed by nanoshell plasmonic modes. Results in Physics, 15, 102744.