Ultrafast plasmonics using transparent conductive oxide hybrids in the epsilon near-zero regime

TL;DR

This paper explores ultrafast plasmonic phenomena in transparent conductive oxides near their epsilon near-zero regime, revealing unique reflection, guiding, and excitation properties of surface plasmon polaritons with high modulation capabilities.

Contribution

It introduces a novel surface plasmon polariton mode in epsilon near-zero regime materials that can be excited without traditional couplers and demonstrates ultrafast control of this mode.

Findings

Total external reflection and air-guiding in epsilon near-zero regime

Excitation of a new surface plasmon polariton mode without prism or grating

Ultrafast modulation amplitude of 20% achieved

Abstract

The dielectric response of transparent conductive oxides near the bulk plasmon frequency is characterized by a refractive index less than vacuum. In analogy with x-ray optics, it is shown that this regime results in total external reflection and air-guiding of light. In addition, the strong reduction of the wavevector in the ITO below that of free space enables a new surface plasmon polariton mode which can be excited without requiring a prism or grating coupler. Ultrafast control of the surface plasmon polariton mode is achieved with a modulation amplitude reaching 20%.