Extreme local field enhancement by hybrid epsilon-near-zero–plasmon mode in thin films of transparent conductive oxides
Abstract
Epsilon-near-zero (ENZ) materials display unique properties, and among them, large local field enhancement at ENZ frequency is of particular interest for many potential applications. In this Letter, we introduce the concept that a combination of epsilon-near-zero and surface plasmon polariton modes can be excited over an interface between a dielectric and a single ENZ layer in a specific frequency region, which can lead to extreme enhancement of local electric field. We demonstrate it with a systematic numerical simulation using finite element analysis and consider two configurations (Kretschmann configuration and a grating configuration), where an indium tin oxide (ITO) layer is sandwiched between two dielectric slabs. We confirm the formation of a hybrid mode at the ITO–dielectric interface at the wavelength of ENZ, as the ITO layer thickness reduces. The hybrid mode provides both high confinement and long propagation distance, which makes it more attractive for many applications than just a pure ENZ mode.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Oct 12, 2020
- Source ID
- 10.1364/ol.402647
Entities
People
- Alexander Baev
- Innem V. A. K. Reddy
- Josep M. Jornet
- Paras Nath Prasad
Organizations
- Defense Advanced Research Projects Agency