English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

The Rayleigh-Modal method is used to calculate the electromagnetic fieldwithin the grooves of a perfectly conducting, rectangular-shaped 1D diffractiongrating. An \emph{enhancement coefficient} ($\eta$) is introduced in order toquantify such an energy concentration. Accordingly, $\eta >$1 means that theamount of electromagnetic energy present within the grooves is larger than thatone will have, over the same volume, if the diffraction grating is replaced bya perfectly reflecting mirror. The results in this paper show that $\eta$ canbe as large as several decades at certain, often narrow, ranges of wavelengths.However, it reduces to approximately 20% under sunlight illumination. In thislatter case, such values are achieved when the \textit{optical spacing} betweenthe grooves $dn$ is greater than 500 nm, where $d$ is the groove spacing and$n$ is the refractive index of the substance within the grooves. For $dn$smaller than 500 nm the enhancement coefficient turns negligibly small.

Light trapping within the grooves of 1D diffraction gratings under monochromatic and sunlight illumination