Terahertz and infrared nonlocality and field saturation in extreme-scale nanoslits

Ferran Vidal-Codina, Luis Martín-Moreno, Cristian Ciracì, Daehan Yoo, Ngoc Cuong Nguyen, Sang Hyun Oh, Jaime Peraire

Research output: Contribution to journalArticlepeer-review

2 Scopus citations

Abstract

With advances in nanofabrication techniques, extreme-scale nanophotonic devices with critical gap dimensions of just 1-2 nm have been realized. The plasmonic response in these extreme-scale gaps is significantly affected by nonlocal electrodynamics, quenching field enhancement and blue-shifting the resonance with respect to a purely local behavior. The extreme mismatch in lengthscales, ranging from millimeter-long wavelengths to atomic-scale charge distributions, poses a daunting computational challenge. In this paper, we perform computations of a single nanoslit using the hybridizable discontinuous Galerkin method to solve Maxwell’s equations augmented with the hydrodynamic model for the conduction-band electrons in noble metals. This method enables the efficient simulation of the slit while accounting for the nonlocal interactions between electrons and the incident light. We study the impact of gap width, film thickness and electron motion model on the plasmon resonances of the slit for two different frequency regimes: (1) terahertz frequencies, which lead to 1000-fold field amplitude enhancements that saturate as the gap shrinks; and (2) the near- and mid-infrared regime, where we show that narrow gaps and thick films cluster Fabry-Pérot (FP) resonances towards lower frequencies, derive a dispersion relation for the first FP resonance, in addition to observing that nonlocality boosts transmittance and reduces enhancement.

Original languageEnglish (US)
Pages (from-to)8701-8715
Number of pages15
JournalOptics Express
Volume28
Issue number6
DOIs
StatePublished - Mar 16 2020

Bibliographical note

Funding Information:
Ministerio de Ciencia, Innovación y Universidades (MAT2017-88358-C3-1-R); Gobierno de Aragon (Q-MADS); National Science Foundation (EECS 1809240, EECS 1809723); Air Force Office of Scientific Research (FA9550-16-1-0214, FA9550-19-1-0240).

PubMed: MeSH publication types

  • Journal Article

Fingerprint Dive into the research topics of 'Terahertz and infrared nonlocality and field saturation in extreme-scale nanoslits'. Together they form a unique fingerprint.

Cite this